I'm on my second Android phone. Had a Hero, now have a Desire. I do charge it every night, but then I work 4 hour shifts and use it on my commutes so it does get a bit of a work out, and does last until I get home to plug it in. I use the control panel widget and keep things like Bluetooth turned off if I'm not using it, and turn off the backlight if the battery is getting low and I'#m in a well lit room - just got to remember to turn it back on before you go outside or you'll never see the screen! If you go into settings you can see what applications are running - you might be surprised. Some of my apps stay on in te background or boot up when the phone is switched on even if there's no need, like games etc, so I rturn those off unless I want to use them.
There are spare batteries available and desktop charging docks that charge both the phone and the battiery, but as others have said it got better after a week or so, so I didn't bother getting them in the end.
These are the Andriod apps I'm using:
Calorie Counter
Compass
doubleTwist (music player which allows you to sync iTunes playlists from your pc)
eBuddy (for msn messenger and Facebook chat)
ElJay (client for updating LiveJournal)
FeedSquares (app for Google Reader)
Foursquare
FxCamera (allows you to take Polaroid and ToyCamera style photos)
GDocs (for editing and syncing Google Docs)
Goggles (Google visual search, very cool)
Google Sky Map (shows constellations based on your location)
Last.fm
mooLa (budgeting and finance tool)
Movies (movie reviews and times)
My Days (to track periods etc)
myPlayer (BBC iPlayer)
Google Navigation
Photoshop Mobile
Springpad (to do lists and notes)
Talk to Me (translator)
and these games:
Abduction!
Flood-It!
Jewels
LineUp
Mahjong
Mazeoid
Poke A Mole
Traffic Jam
Trio PRO
Word Drop
Zombie, Run!