Sure, you could pay iTunes two bucks for every episode of The Office you download to your PC. Or you could add a TV tuner and record unlimited shows--in high def!--free of charge. eCost has the Viore Portable HDTV Tuner for just $55, a steal at twice the price.
Just plug this USB tuner into your desktop or notebook, then connect an analog cable feed or the included ATSC antenna. The latter lets you pull down HD channels right outta thin air (provided you live in a metropolitan area).
To record shows for later viewing, you'll need Windows XP Media Center 2005, Windows Vista Premium, or Windows Vista Ultimate: Microsoft's Media Center (which is baked into those three operating systems) offers killer DVR capabilities. All you have to do is supply a tuner like this one. It even comes with a remote.