Photo credit: Maxxyustas

1. Coccinella: Connect to major instant messaging services from any operating system
2. Wikidot: Create free wikis for unlimited people with 100MB of storage space
3. Nexdo: Free service allows teams to create pages, exchange links and share files
4. Jagbox: Upload any file, set the expiration time and share the link with anyone

1. Coccinella
   
   Coccinella is an open-source chat client that runs on Windows, Mac and Linux. It can connect any Jabber/XMPP instant messaging server, as well as normal services like ICQ, MSN Messenger, Yahoo and AIM. It supports file transfer, group chat, emoticons and whiteboard. The setup file is just 6MB and can be downloaded and used for free.
   http://www.thecoccinella.org/





2. Wikidot
   
   Wikidot is a free web-based service for creating wikis. In a matter of seconds, after a free and simple registration, you can create your wiki page, where you and your team can create an unlimited number of page and upload files for a total space of 100MB. Users can interact with private messages and can edit any page, and any editing will be notified to the others via RSS feed. The service is free to use.
   http://www.wikidot.com/





3. Nexdo
   
   Nexdo is an online service where teams of people can create and edit pages together, exchange links and files. Any member of the team can create or edit any page, and any change will recorded for other people to see. The free version allows you to create a group of five people and share files up to 10MB (total space). Check other versions here.
   http://www.nexdo.com/





4. Jagbox
   
   Jagbox is a web-based service that anyone can use to share files for free. Without any registration you can send any type of file up to 100MB to anyone in four easy steps: just select the file you want to share, set the expiration time after which the file will be deleted, click upload and share the link with your friends. The service is completely free to use.
   http://www.jagbox.com/