Personally, i have google maps, live search, twitterberry, viigo, and weatherbug.
i had facebook but didn't care much for it, same with aim and yahoo and googletalk. i text more than im chat so yeah. i also had blackberry maps but deleted it for the google maps.
talk about good applications that are cheap or free! i just don't wanna overload my 8120 lol
Weathereye
gmail
google
opera mini
tv guide
nav4all
viigo
tellme
jivetalk
google maps
espn
crackberry
wikipedia
tetris
pacman
kings poker
flashlight pro
bb tipper
Mobipocket Reader -Free Reader. Books Cost
Viigo - Free
Google Maps -Free
Live Search (Microsoft) -Free
Follow-Up! - $19.99 (Sets Alarms and reminder for emails that you need to take care of.)
SoftReset -Free
BubblePopper
Mini Monitor (Data-Volume Counter)
Flashlite Pro
Facebook
CrackBerry Shortcut
Google Maps
VibAndRing
SMS Display ON
...and a lot of unreleased utilities
after trying out 4.5 and rolling back to 4.2 I minimized a bit.
KeePass
google maps
live search
mobipocket
flickr uploader
twitterberry
facebook
webmessenger
viigo (which seems to be broken)
opera mini (rarely used)