In this article on Instructable is explained how to turn a ti calculator into an intervalometer for a DLSR, by simply using its communication cable and writing a little script: Turn a TI Graphing Calculator into an Intervalometer and Create Time Lapse Videos.
The author tested it with a ti-83+ and a Canon Rebel, but ti-84, ti-89 and other cameras are also discussed in the comments. Other combinations can be found all over the web.
Geeks3D recently posted a couple of posts on billboards rendering using vertex shader or geometry shader, and particle rendering performance when using point sprites or geometry shader.
This 8mn video shows the initial 30s after ignition at the launch of the Saturn V rocket, carrying the Apollo 11 mission on July 16th, 1969.
Apollo 11 Saturn V Launch (HD) Camera E-8 from Spacecraft Films on Vimeo.