I don't know if it's possible, but I want a universal remote that can be had for under $50. I want it to control my Audio Receiver, DVD Player, TV, Satellite, and Cable. Most important for me is for the remote to be able to access the guide screen from the Satellite or cable receivers. Right now I have to use 3 remotes (one for cable/tv, one for the satellite receiver, and one for the audio receiver).

Also, what is a "learning function" that I sometimes see advertised with a remote?

The learning function means that the remote doesn't need a number code preset to a particular device, rather it can be tought the IR commands button-by-button. I would not consider getting a universal without this feature, as it makes them "future-proof" by letting them handle devices that have not been produced yet.

The Sony RM-VL600 is a good, 8-device universal that can be bought for under $20.00