For all you Old School DIY viewer craftsmen out there.

I got a pair of these for $5 ea. at my local Five Below store

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=380227988489#vi-content

http://www.handy-gadgets.com/mt/mt-search.cgi?IncludeBlogs=39&tag=25%20LED%20Super%20Bright%20Square%20Worklight&limit=20

They have a 5x5 matrix of very bright, white LEDs and run on 3 AAAs. They also have a versatile swivel/stand hook and magnet on back for different work environments.

Place a pair together on a table, click them on and hold your STL viewer a few inches over them until the beams all fuse. They deliver 2-3" squares of intense white light at about the right interocular distance.

The more handy among you here can probably take these apart and make a nice viewer mod.