Even XKCD made a great comic on this issue... a while ago.
That is all about to change now that the TI-8X line of calculators is 22 years old. Their new TI-84+C-Silver edition will come with a 320x240 16-bit color display, 3.5MB of flash ROM, and 21KB of RAM. I am going to dust off my graphics programming skills from 1994 and see what fun stuff I can make on this puppy!
Ars has a good preview of the device along with speculation on why it took so so so very long for TI to finally bring calculators up to a level of technology that could have been delivered a decade ago.