AskSunday are a quick task outsourcing company. They offer plans including a number of "tasks" which typically take 20 minutes each to complete. Starts from $17/mth for about 10 tasks. They have project based plans "Sunday Projects", price on request.
ProjectPier is a Free, Open-Source, self-hosted PHP application for managing tasks, projects and teams through an intuitive web interface. An opensource version of basecamp! Looks pretty basic, not nearly as ajaxy / designed as 37 signals.
Collabtive is an open source clone of BaseCamp (the 37 signals project management software) built in PHP backed by MySQL.
Webgrity is an outsourcing company. I think they do lots of work on elance and other freelancer sites.
Globe Task is a virtual outsourcing company. Rates start at $12 per hour for pay as you go and drop to $8/hour for 40 hours / month.
DoMyStuff.com is an online outsourcing site where you post jobs and people bid on them. Like RentaCoder.com but for any type of task.