Dan is getting rid of his cable box and is looking for an analog to digital converter for his over-the-air antenna. Leo recommends the ChannelMaster. It's like a TIVO for an antenna. This is a great option for cable cutters.
Dan should also get an ATSC Tunner, which will take the current over-the-air signals and convert them for use with an analog device. Dan should visit Antennaweb.org. He can enter his zip code and find out what channels he'll be getting. Another site to check out is TVFool.com.
Leo recommends pretending that he has an HDTV and buy everything with HDMI. Then he can use an HDMI to analog converter from MonoPrice.com until he can get an HDTV to replace the older one he has. The best analog connection to look for in the converter is component. The next best is S-video, and then composite. Newegg has an HDMI to Component converter for $35.