There's no shortage of whiteboarding apps and tools that give teams a simple online space to collaborate and share documents in real time, but few of them provide screenshot and comment tools, multi-user editing and iPad optimisation the way that Conceptboard does.Conceptboard allows you to upload files directly to the board, invite others to view and work on a document or image with you in real time, and lets those other users comment and share their thoughts while working. You can also use the service as a workshop and turn on "presentation mode", which will disable editing features until the leader turns them back on. The service also works perfectly on the iPad, so even workers on the go can chime in and participate.
Conceptboard is free for up to 25 boards. Pro accounts ($US8/month) offer unlimited boards, password protection and SSL encryption. Enterprise accounts ($25/user per month) includes both extended features and adds corporate messaging support.