What we're watching tonight:
- CW (1080i) has Reaper at 8 p.m. and 90210 at 9 p.m.
- Fox (720p) has American Idol at 8 p.m. and the season finale of Fringe at 9:04 p.m.
- History (720p) has the season finale of How the Earth Was Made at 9 p.m. and Life After People at 10 p.m.
- Discovery (1080i) airs Deadliest Catch at 9 p.m. and The Alaska Experiment at 10 p.m.
- HBO (1080i) has The Alzheimers Project at 7 & 8 p.m.
- TLC (1080i) has 18 Kids & Counting at 9 p.m.
- CBS (1080i) brings NCIS at 8 p.m. followed by The Mentalist at 9 p.m. and Without a Trace at 10 p.m.
- ABC (720p) drops in According to Jim at 8 & 8:30 p.m., followed by Dancing with the Stars and Cupid at 10:02 p.m.
- Sci Fi (1080i) slides in ECW at 10 p.m.
- TBS (1080i) brings My Boys at 10:30 p.m.
- FX (720p) has Rescue Me at 10 p.m.
- TNT (1080i) doubles up on NBA Playoffs action with Magic/Celtics at 8 p.m. and Rockets/Lakers at 10:30 p.m.
- Versus (1080i) has NHL playoffs action with Boston/Carolina at 7 p.m. and Detroit/Anaheim at 10 p.m.