I just signed up for Palringo at http://www.palringo.com/. It is great. My friends and co-workers can talk to each other with a push of the button. Palringo is an instant messenger that works with all the common IM servers such as AOL, MSN, Yahoo and others, but is also Has a push to talk feature I find to be great. I can load it on my Motorola Q phone and my wife has it at the house. If she needs me she just pushes to talk to me and it comes out in my bluetooth headset. There is a low battery usage mode so it doesn't wear out my phone battery, but I think it only poles every 30 seconds are so in that mode. However, it still works great. You can also send photo IMs to each other. Best of all, It is free software. So try it out. I think you will find it useful in some work situations, and fun for friends and family to keep in touch. I don't have time to explain all the features such as group IM's and other things, so check it out for yourself.
Don't forget to checkout my business website at http://www.itofms.com/