HiTask is a(really simple collaborative task management tool for small groups. Members can create tasks, meetings, reminders, notes, and birthdays to add to their own schedule or assign to others. The entire interface is drag-and-drop, and any actions by team members will instantly be reflected on your tasks page. It's a mix of a scheduling app and to-do list tool that's dead simple to use. In testing, we were making and managing several projects in less than five minutes without reading any documentation, which bodes well if you're collaborating with non-tech-savvy people.
Assigning tasks to other users is really simple. Once you've created a task, you can just drag it over to the group member's name. You'll get a note on the task letting you know who you've assigned it to, and as soon as they're done with it you'll be notified in real time. Likewise, when a group member assigns something to you, it will show up on your schedule, along with a note of who it's from. The one thing missing from HiTask is the option to view other members' schedules, which would be helpful--especially for gauging how much is on someone's plate.
If you do need to talk, there's a built-in chat module, which is limited to one-on-one. There's no way to group chat, or share files like you get with some more advanced group collaboration tools like BaseCamp, and activeCollab, but HiTask is pretty early in development.
HiTask has both a free and premium service. The free service reaches its limit at 10 tasks, making it little more than a demo. The $15 a year service provides unlimited tasks, group members, and projects. See the screenshots after the jump.