Mr. Blake (above) mentions a very interesting strategy. If you play online poker, you can record the screen during your play. You can then review the footage at a later time and see where potential weak points are. This will obviously not be 100% objective, depending on your own internal biases. But you are much more likely to catch things that you would not have only relying on memory. At the very least, you can get an idea of patterns of hands you prefer to play vs position on table vs available chipstack, etc.
If you use bsr screen recorder (bsrsoft.com) or even snagit 11 (techsmith.com/snagit.html) now comes with screen recording, you can save files in avi format and probably get 1 hour of video with for under 100 MB at full screen; less if you use smaller screen recording region size. CamStudio is free if you are on a budget. I do something very similar when evaluating my forex strategies (AwarenessForex.com), but there are a few notable differences. My forex strategy is entirely automated, so I can focus purely on improving the mechanics of the strategy. When filming poker games, you must be mindful of your real-time emotions. Make sure you are recording sound and don't be afraid to express your true emotions. It will help 'mark' which hands to focus on. Another good thing about video recording is you can skip through video with fast playback. VLC player (VideoLan.org) you can set the speed of playback, or just drag the timeline to skip through hands.
I should also mention that poker odds calculators, such as Poker Tracker that can also record your hands for deeper analysis, including calculated odds for your hand at each stage from preflop to river.