Easily one of the most helpful Internet resources for beginning-to-advanced 3D modeling. There is a large contingent of Trek-related material on this site, but there's really no limit to what is acceptable there. The reason there is so much Trek stuff there is really very simple: 3D modelers need lots of reference materials and Trek is the largest and most closely-studied sci-fi phenomenon out there, with literally tons of reference pics for everything from ships to props. Just as with anything else which requires training and experience, it is best to follow in the footsteps of those who've gone before you. Newbies and pros tend to stick with the Trek stuff for this reason.
Conversely there is also Star Wars material, original 3D meshes and concept designs which defy categorization that can be found at this site- both in the WIPS (Works in Progress) and downloads sections.
The Forums section is the real heart of this place. One can get info on various modeling techniques, rendering tips, reference materials, lighting tips, general 3D community news, guidance, critiques and just about anything else you could imagine necessary for the student modeler. Pro's and newbies alike participate in all the message threads and the "feel" is very similar to what can be found here at E2- everyone pretty much helps each other improve their craft with supportive and constructive criticism and insight.
The 2D and 3D Art Galleries are full of top-notch work which can serve as inspiration for anyone who is interested in creating their own models but is lacking in ideas. What's more is that many of those images make for some great backgrounds on your computer.
Membership to the site is free, downloads are free and participation is welcomed. You will find the work of some of the best 3D modelers on the 'net at Scifi-Meshes.Com, all of whom are eager to share their experiences and expertise with those who are willing to learn.
Word to the wise: learn some German. A large number of the pros are from the Deutchland and their English is sometimes hard to follow. That said, everyone's dedication to the site is 100% genuine. If you're interested in 3D modeling and are hungry for help, these guys are there almost 24 hours a day. Their tutorials section is especially amazing.
http://www.scifi-meshes.com