I did a write up on my home-made top hoist. I used 2 ratchet straps, 2 bike hoists bought from Menard's, some 2x4s I had laying around for extra support (didn't match up w/ my ceiling rafters width-wise) and some long wood screws. Took about 2 hours or so to get it exactly the way I wanted it; its not perfect but it works. I can take my top off in less than 15 minutes by myself. All for less than 30 bucks.
(sure there's a joke there...)