Here's a simple use for Quicksilver. Create a new trigger with the first pane set to your music library. Set the second pane to "Search Contents" and now you can load any song while working in any application. Shouldn't iTunes come with this feature built in? Update: Another way to do this is with the iTunes plugin for Quicksilver. Invoke QS and start typing "iTunes", then right arrow in to see a list available options like browsing artists, tracks, genre etc.
If you're not using keyboard shortcuts and tricks, you are wasting precious time that could be better spent on YouTube. Here's a couple of my most used keyboard shortcuts for the mac. Safari Specific shortcuts to switch between tabs in Safari to jump to the search field in Safari command and '+' or '-' to change the size of text in Safari General tricks Hold down the ctrl key while scrolling the wheel/ball on your mouse to zoom your display in and out (I wish my PC had this) to lookup a word in the built in dictionary cmd and tab to bring up the application switcher Technorati Tags: Apple, Hardware, Mac, OSX, Tip, Trick
Remember back when Steve Jobs introduced us all to Spotlight. He did a demo that seemed like magic. He typed in a word and Spotlight found audio, video, photo and text documents related to that word. I was amazed and rushed to get Tiger installed on my mac. What a let down when I realize that this only works if you have tagged your files with Spotlight comments.