PowerPC :: How To Extend My IBook's Useful Lifespan?

My 2004-era G4 iBook, bought as a refurb a couple years ago, is still chugging away just fine, but I'd like to maximize its future usability without pouring a ridiculous amount of money into it. My thoughts so far:

-Max out the RAM. It's just a stock unit, so the result should be a nice performance bump for not much money.

-Put it on a ventilated stand when using at home. The iBook doesn't get blazing hot, so maybe this isn't a big deal, but the battery area sure gets warm, even when plugged in. Might make a difference over time.

-Proper battery conditioning. I've just been letting it run down about halfway, then charging it up again as needed. I probably need a more by-the-book method.

-I might hook it up to an external monitor at home to spare the iBook's LCD screen unneeded use, except I don;t know whether I can actually put the ibook screen to sleep while the external display keeps running....It might not make much difference anyway.

-Don't drop it.

Other things I can do to keep my iBook viable and healthy?