Photo credit: Kirsty Pargeter

1. radiusIM: Web service that shows you the geographic location of your buddies and lets you send instant messages to them
2. Voxlib: Use Skype from your mobile phone, without having to download anything on your device
3. V4S: Voice messaging platform that enables you to send and receive voicemails
4. Instantstream: Online collaboration system which allows you to display synchronized PowerPoint slides and web conferences

1. radiusIM
   
   
   
   radiusIM is a free web service that shows you where your buddies are and lets you send instant messages to them. Once you sign up, simply login to radiusIM and choose your geographic location. Your friends will show up on the friends list as icons on a map. You can message your friends on MSN, AOL and Yahoo! Messenger. RadiusIM is a completely browser-based application and requires a Javascript enabled browser, which can be either Internet Explorer 6+, Firefox 1.5+ or Safari 1.2+. Free to use.
   
   http://www.radiusim.com/
2. Voxlib
   
   
   
   Voxlib enables you to use Skype from your mobile phone, without having to download anything on your device. All you have to do is install a software on your computer, which will connect Skype and your mobile. If you call your SkypeIn number to access Voxlib, the only costs you will incur when calling a Skype contact will be for minutes of mobile usage billed by your mobile operator. SkypeOut charges will also apply if Voxlib is used to call a regular telephone. If you prefer not using SkypeIn to access Voxlib you can also use SMS. Watch the demo to know more. Free download for a limited time.
   
   http://www.voxlib.com/





3. V4S
   
   V4S is a voice messaging platform that enables you to send and receive voicemails. V4S can also send you email or SMS alerts containing a link to new messages as they come in. You can check how many messages you have even from devices that don't have a streaming audio player (like some mobile phones). V4S will take messages for you as long as you're logged on to Skype from the always-connected Windows XP machine where you installed V4S. Free to use.
   http://orb.com/skype/





4. Instantstream
   
   Instantstream is a web communications service that provides "Streamphone", a system which has audio and video features and allows you to display synchronized PowerPoint slides, perform group calling and sales presentations, collaboration, chat and specialized web conferencing services for 1-12 presenters. Streamphone can broadcast to more than 5.000 viewers. Check out the list of the subscription plans, starting from Video+Audio at $0.20 per minute (Audio only comes at $0.06 per minute). If you register for a free account you will get $10 free minutes.
   http://www.instantstream.com/