Photo credit: Maxxyustas

1. Easy Message: Smallest downloadable multi-protocol IM client allows you to connect to the major IM networks
2. Mindomo: Online mind-mapping tool lets you create and share mind-maps with your team
3. SmartSheet: Online task manager and spreadsheet editor allows you to collaborate with your colleagues
4. Wippien: Multi-protocol instant messenger with VPN enables you to chat and collaborate with your friends

1. Easy Message
   
   Easy Message is the smallest downloadable instant messenger, just 240 kb, that allows users to chat on multiple instant messaging networks from one place, supporting MSN, AOL, ICQ and Yahoo. Its main features are file transfer, group chat and mail notification. It is completely free and you can download it here.
   http://www.easymessage.net/





2. Mindomo
   
   Mindomo is an online mind-mapping tool that you can use to create and share mind-maps with any PC and browser. Mindomo free version lets you store up to 7 maps and invite as many people as you want to see and edit them. You can also check out other versions.
   http://www.mindomo.com/





3. SmartSheet
   
   SmartSheet is a web-based spreadsheet editor that lets you create and share spreadsheets with your team mates. With the free plan you can create and share up to five spreadsheets, with an unlimited number of people. You can use it for free or check the advanced plans.
   http://www.smartsheet.com/





4. Wippien
   
   Wippien is a full featured instant messaging client that supports the major chat protocols, including AIM, MSN, Yahoo!, GTalk, Jabber, and ICQ. The unique feature of Wippien is that it has a VPN (Virtual Private Network) baked right in and can be used to manipulate your online buddies' network shares, printers, desktop, and more. Free to download
   http://wippien.com
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