I just found out how to drastically shorten the delay between closing my laptop and seeing the pulsing "sleep" light:

[W]hen my Mac goes to sleep I have to wait for it to write most of the 4 GB of RAM to disk. A fellow engineer just showed me a faster way to make the Mac sleep […].

Like Mike, I like to be sure my laptop is actually sleeping before slipping it into my bag so it doesn't run down my battery or dangerously overheat. I just did a quick test, and this tip reduced my wait time from over 40 seconds to about five. That long wait really detracted from the feeling of having an on-the-go machine.

I save frequently and compulsively, so I'm not worried about losing data if I accidentally let the battery run down, which is pretty rare. It usually happens precisely because I didn't didn't have the patience to check that the laptop was really sleeping, though a couple of times it was because I had unknowingly jostled the lid open while it was in my bag. The biggest pain about losing my RAM state would be waiting for my dozens of browser windows to reload, but I seem to be doing that regularly anyway when Firefox suddenly decides to get flaky.

I also plan to check out SmartSleep, mentioned in the comments.

(Via Ranchero.)