...or...kill 2 birds with one stone. If you have cable internet (only), you can still have access to the QAM channels without any tv cable service (only internet). That's what I do.
Clear QAM is basically the same thing as OTA, except you don't need an antenna. Most of the channels are local network channels that you would get OTA. And most (not all) are HD. Plus stuff like PBS, some local news/weather channels...etc. Its nice to have as you don't have to mess around with an antenna. Just get the coax into your TV and do a scan (your TV needs to have a QAM tuner...almost all new sets have them...).
FCC rules and laws are about as muddy and archaic as they come. Generally, the cable companies are supposed to offer a certain amount of local channels over their QAM networks "in the clear"...meaning you don't need a box to descramble them.
It works pretty well. Sometimes they will change the channels on you at random, requiring a rescan from time to time. But I rarely have issues with it.
Note: to be clear, if you have NO cable subscription at all, it is highly unlikely you'll have access to clear QAM. You'll need at least the most basic package (which usually isn't advertised and is like $10 a month), or internet service....