[Blind-sysadmins] Accessible project management tools.

Hello, I'm looking for a project management tool and I'm hoping someone here might have a suggestion. MS Project isn't a viable option at the moment. Required features: * Add contributors from within and outside this organization. * Standard fields such as task name, dependency, assigned to, start date, end date, total time, complete. * Add notes to tasks. * Highlight tasks assigned to the user. * Must be fully accessible. * Preferably web based. Any ideas? Thanks Darragh