http://i607.org/wiki/doku.php
a lot of info there, or you can head over to howardforums.com, there is a 60+ page thread there about stuff for the blackjack, but, the wiki pretty much sums up the entire thread. Depends on what type of business you are in, Facade is good for handling your contacts better then the standard windows mobile way.
Killing time? the Nintendo emulator is awesome, also, buy a 1gb sd card and store most everything on there, as the blackjack only has 50ish mbs of memory.
I also have Windows Live, Google Earth, Dont Forget, and Alphadial.
Alpha dial lets you put in any combination of numbers / letters and translates it into a phone number. Like put in 1-800-COMCAST, and hit dial, it'll ask you to confirm the number, then the phone dials it for you.
The Blackjack doesn't alert you, if you have a missed call/e-mail/sms, but Don't Forget will do it for you. It doesn't take up much memory, and I leave it running all day.
Also, I'm not sure which battery you have, but the regular battery, when you first get it sucks. It has almost 0 battery life, but each time you recharge it the life gets better, I can get a day and a half on a single battery now.
Also, I haven't seen many sites for home screen's for the blackjack, but you can load up a MotoQ homescreen and it works perfect for the blackjack.