Ex Astris Scientia is a fairly amazing Star Trek website run by Bernd Schneider, an engineer in DÃ¼sseldorf. The site is full of ultra-geeky Trek stuff, including fleet charts showing various spacecraft designs, the Starfleet Museum which "[preserves] historically important Starfleet ships for future generations," and the Treknology Encyclopedia.
Now, I'm as much of a Trek fan as the next guy (TNG rules, thank you very much), but this site represents some seriously impressive fan research. My favorite section of Schneider's site is the Galleries, which contains amazingly thorough representations of all things Trek, from screen captures of various items on the ships to schematic drawings of different areas of the ships. Here are a few samples from the Computer Displays and Interfaces gallery:
Enterprise-E deflector control:
Phoenix computer console:
There's lots more where that came from. Trek fans, I salute you.