And another... it is not very obvious but when you are editing the Speed Dial pages (favorites) in the Phone application, you can drag and drop favorites between pages of favorites. Pick em up with the stylus and drop em on another page.
Option + Up or Option and Down in the Launcher is page-up and page-dn respectively. Some other apps support this too.
This is not really a built-in apps tip but it shows how to reveal the possibilities of the 650. i.e. what filetypes are handled by the 650 and where files need to be stored to take advantage. There are two applications that help to reveal this information (both read the Unsaved Preferences file AFAIK):
PalmInternals
http://www.palmgear.com/index.cfm?**...1&prodID=46801
and even better:
DefaultDirs -
http://www.chocopoolp.com/others.html. You need an SD/MMC card inserted for this to work.
DefaultDir reveals that the Treo 650 handles these extensions:
.qt - quicktime movies
.rm, .ra, .rms, .rax and .rnj - Real Media
.mpeg, .mpg, .avi, .mov, .jpg, .jpeg, .tif, .tiff, .gif, .bmp, .rle
.wav, .mp2, .mp3, (.ogg if you have pTunes installed)
.pqa - why even bother with palm.net gone?
.prc and .pdb - obviously
.asf, .dib, .jif, .jpe, .mpa, .mpe, .mv1
A few audio oddities - .plm, .pom, .sa1, .sp1, .tkm
mpeg video formats: .3gp, .3g2