I just picked up a Cycle-ops magneto on craigslist for $99. It is high quality and works great. I just have to get over it being such a boring ride. I do 1 minute intense and then a 3 minute cool down light peddling and repeat that for 45 minutes every night. It has kept my stamina up over the winter.
I've found using my iPad to watch movies helps a little to counter the boredom.