Choosing an open source license

I have an open source project (NXmlSerializer) which I want to use at work. This lead to a good discussion with other developers and managers about open source development, how both the company and the community win, and has made me spend some time taking a closer look at which open source license I use. The selection points I've come up with are:

• Avoid any liabilities
• Allow free use
  
• Allow commerical use
• Encourage collaboration

I've used the GPL license in the past, but now I'm not happy with the constraints this license puts on commercial use. Appropriate if competitive but the intent is to collaborate so I'm looking at licenses like the BSD.