You often hear that to work with graphic displays on the Arduino platform you need to use a Mega or other high-performance board. I got curious about how much you can actually get done on an a measly Uno and similar boards based on the classic ATmega328P. You can find the ongoing results on my wiki.
The story so far: 128×64 and smaller monochrome displays are usable. The smallest TFT displays much less so.