I may have mentioned this before but the only software I am buying recently is software for my Treo 600. I am finding so many useful things to get, I going out and buying the full versions when the trials are over.
I just bought Verichat. it allows you to chat over GPRS. You can use AIM, MSN, Yahoo, and ICQ. If you are not actively in the program, but logged onto their proxy server and someone sends you an IM, you get a SMS message with the IM. You then can sms back or enter the program and chat. Regular chatting does not use up SMS messages. it rocks.
I also got Call Shield Lite for the Treo 600. It allows me to identify anyone or any group with distinctive rings. It also allows me to hang-up, send to voice mail or answer any call by a number of parameters. you do this by group, person, or phone number. I have someone who keeps calling with a wrong number. I programed the software automatically hang up on them before the phone rings. It is so crazy, how cool this software is.
I am going to buy jabber software so I can use work’s jabber system on the Treo. I haven’t tried that out yet, but it looks good.