You've Gotta Be Kidding Me!
The iPod was the best thing to ever happen to my music collection. When you have nearly 1,500 CDs, and only a Diskman and 5-CD changer, you don't get to randomly sample your music nearly as well as you do with the iPod. However, getting the most out of your iPod requires organization of each track and your use of playlists, both in iTunes and with On-The-Go on your iPod.
I have 23,000 songs in my iTunes library and 16,000 songs on my iPod. Through the use of playlists by musical genre, artist, or other factor (Guilty Pleasures, which I label in the iTunes Grouping field, for example) I can always find something that fits my mood. If I need to wake up, I'll put on a list filled with aggressive dance tracks. If I want to mellow out, I'll put on some classical or Pink Floyd.
And if I'm not sure how I feel, I put the iPod on Shuffle (by album), and just let it play. If I hit a song that I know I won't want to hear again, I rate it with 1 star. I manually manage my iPod so it only loads playlists. All my playlists are set to remove songs with 1 star, and I have a Blacklist playlist of 1-star songs on iTunes that I can occasionally review if I want to reinstate anything I may have removed in haste. And with iTunes 7, I've also put in a Skip blacklist - if I skip a song more than 5 times, it gets taken off my iPod and goes into the Blacklist. If it's something I skipped because I just didn't want to hear it at the time, but I don't want it off my iPod, I'll reset the skip count in iTunes.
While this has taken a lot of thought and work with both iTunes and my iPod, the end result is that I always have music with me that I want to hear, and I can easily access whatever best suits my current mood. I've never enjoyed my music collection more, and I cannot ever imagine living without my iPod now.