My latest was actually pretty simple -- a slightly used 80gb drive, $49.95 for a bit of software, and $10 worth of cables, and a pile of other stuff that I already had. The result, in a hardware sense is that my record player now plugs into the sound card on a recently-built spare computer (scrounged from various bits sold on the campus forsale newsgroup), and the sound out from the sound card goes to the stereo system.
This is not, however, the cool bit. The cool bit is that I can play records on the record player, and the aforementioned software will record them and then use some apparently relatively advanced signal processing tricks to remove almost all of the crackling and popping and hissing that old records often have -- it really works quite impressively well -- producing a clean audio track that I can then write to CDs that I can play in my car, or MP3s that I can keep around on my hard drive and play later (or bring to my office and play there when I'm working late at night).
So, meanwhile, I bought some more records at the Friends of the Palo Alto Library book sale ... about three dozen, for $10. Whee! *grin*