What can you do if you have a really small kitchen, but can't afford to do a major kitchen remodel, such as knocking down any walls or doing an addition to your home?
Well, you make the most of what you have. We gave that little kitchen a complete makeover.
This is what we ended up with:

In our case, we had a small L-shaped kitchen in tiny rectangular room which had three doorways going into it, and two windows. The refrigerator was tucked into a nook at right angles to the hinges of the back door, which meant if you had the fridge open, no one could come in (likewise if someone had the back door open, you had to shut it to get to the refrigerator).
The kitchen floor plan was roughly like this:

That empty space under the window on the back door wall was never actually empty. When we looked at the house before we bought it, the people who owned the place had a cart with a microwave and all kinds of junk piled up there. (I don't think these people ever watched Design to Sell or anything like it.) When we moved in, we stuck a small drop-leaf table there for a while and I think we used that for our microwave.
The first thing we knew we had to do was replace the refrigerator. The one that came with the house was nasty. But when our new refrigerator was delivered, we discovered a problem: it was too big to fit in the nook the old refrigerator had occupied. We considered knocking down the wall adjoining the hallway that formed the side of the nook, but we thought it might be load-bearing and didn't want to mess around with it. We thought about shaving down the walls or putting in paneling instead of sheetrock to give us a little more room. But then the delivery man said, "why don't you get a smaller refrigerator?" Duh. I guess we had thought we were buying the smallest one, but nope, they came smaller. So we did as he suggested, and were quite happy with our new refrigerator, which we hooked up to the reverse-osmosis drinking water system we had installed. Awsome ice water!
There was one casualty when we got a new refrigerator though. Namely, the cabinet that was above the old refrigerator. The new unit was taller than the old one, and no standard cabinet would fit there. The old cabinet was installed in such a way that the only way to remove it was with a reciprocating saw. then we patched and painted the walls, and put a big rectangular basket on top of the refrigerator where I stored plastic wrap and aluminum foil and the like. It worked out just fine.

The oak finish cabinets looked almost new, but there were not many of them. The laminate countertops weren't so great. The vinyl floor was ugly. We had had all the hardwoods refinished in the rest of the house, which made the kitchen floor look even worse.
We wanted to utilize that wall with the window as a third section of counters and cabinets, a perfect place to add a dishwasher. The one problem that kept us stalled for a while was the height of the window. It was lower than the standard height of countertops. We didn't know how to make the opening of the window smaller because the exterior of the house was nice red brick, how would we ever make it look right?
So what did we do? Well, we added the third length of countertops and the dishwasher, with even a couple more upper and lower cabinets and a little spot on the end by the door with a stool tucked under it as a place to sit. The layout now looked like this:

and as for that low window... we just cut off the sill and otherwise ignored it. It's an old house. Consider it one of its quirks that the window goes behind the countertop a little. That happens to be the only window in the house that we did not replace with vinyl windows. We didn't think an installer would go for it, so we just didn't want to raise the issue.
Luckily, by the way, we found the exact same cabinets that were already installed in the kitchen in stock at Home Depot, so we were able to keep the existing one and add matching ones, including a corner cabinet with a glass door to show off my Port Merion china collection.
We had an industrial vinyl floor installed. It was off-white in color, kind of a parchment-paper texture. It was so easy to clean, and made the kitchen look so much bigger!

We also replaced the old stainless sink with a new almond-colored one (to match the refrigerator and our new dishwasher!), added a faucet coming from the drinking water system, and installed a new stove, replacing the old electric range with a gas one.
We got hung up a little bit on putting in a microhood. The problem was, there were soffits above the old bank of cabinets, and Home Depot didn't have a cabinet short enough to install above the microhood while allowing the microwave to be installed at a proper height above the stove. So we went down the street to Lowes, where we were able to find a shorter cabinet that looked close enough to the rest of our cabinets. Now the microwave was off the countertops, giving us even more working area, plus a nice bright spot in the kitchen with a white stove and white microhood, with nice lights shining down on the stove.
It had become a very sensible, well-layed-out and user-friendly kitchen with just the right amount of storage.
As far as the decor, I used a combination of wallpaper and paint technique. This is where I mastered my favorite faux-painting technique:
mix a little paint with a little glaze
pour it into a roller pan
wear plastic gloves
scrunch up a plastic grocery or department-store bag and dip it in the paint, blotting it on newspapers
pounce the paint-covered plastic bag on the walls.
Of course, I started by rolling on a neutral base coat, and used a dark tan-colored paint for the first layer, then took an almost-beige tan color for the next coat, finally pouncing on a thin coat of off-white glaze which really unified the look.
The colors were chosen to match the wallpaper. I used a tile-and-flowers design paper in place of a backsplash, and I placed the matching border on top of my faux-painted soffits. Using both paint and wallpaper kept the cost of the wallpaper down in there.
We remodeled that whole kitchen for less than $2,000. We did most of it ourselves (with the abundant help of my family), except for installing the gas stove and vinyl floor. By keeping the appliances mid-grade, sticking with the stock cabinetry that was already installed and just adding a few more cabinets, and going with laminate countertops again (but this time they coordinated perfectly with the rest of the decor) we were able to get a really nice kitchen that didn't price us out of the market when it was time to sell.
In fact, that kitchen was a LOT nicer than the kitchen in the house we now have moved into, and I have plans for remodeling this kitchen too, but that is a whole other story.