My personal favorites are:
Easy Money for my banking (Purchased version)
Office Suite (Purchased version so that I can change things)
Score Mobile (being a sports nut)
Trust Go (a phone protector)
Alarm Droid (my alarms are all set up)
Aldiko Premium (Purchased) so I can read my favorite books while waiting to see the doctor, etc. Sometimes I even get to read a whole book while waiting.
Area Code so that I can check an unknown area code when I get those spam phone calls.
There are a few more that have already been mentioned, such as Color Note, that I also use.