Photo credit: Pamanes

1. TeamViewer: Free downloadable application allows you to share your screen and control anyone else's PC
2. MECA: Connect to popular instant messengers at once, and get all your buddy lists into one
3. GrandCentral: Get one number for all your phones, and record all of your calls with a click of a button
4. Exploratree: Create "thinking guides" and use them to collaborate on projects and documents

1. TeamViewer
   
   TeamViewer is a free small downloadable application that allows you to share your screen and control anyone else's PC. After you download the small program, you just start it without any installation: you can then give a code and password to your friends to see and control your PC, or they can give you their code. You can also chat, transfer files, and use it to remote control your computer from anywhere in the world. Free.
   http://www.teamviewer.com/





2. MECA
   
   MECA allows our members to communicate with the other popular instant messaging programs, AIM, MSN, Yahoo!, and ICQ. You can now access your other messenger accounts and consolidate all your buddy lists into one simple messenger interface. It features offline messaging, file transfer, message history, emoticons, and more. Free to download and use.
   http://mecamessenger.com/





3. GrandCentral
   
   GrandCentral is a new web application that lets you link all of your phone numbers to a new special number.That means that someone can call you on your GrandCentral phone number and all of your phones will ring. You can set rules by friends, family, work, and others, defining where the calls should be directed, and you can also record all of your calls in MP3 format by pressing a button.
   Free to use.
   http://www.grandcentral.com/





4. Exploratree
   
   Exploratree is a new online service that allows you to create so-called "thinking guides". Thinking guides are basically blank documents on which you can add images, text, and shapes, and you can share them with other people in real-time, both for document editing, or for other collaboration tasks. You can try it without registering, or sign up to the service to get your work saved online. Free.
   http://www.exploratree.org.uk/