Monetization: ad serving, ad exchanges, ad networks, ad agencies, analytics, ad representation, paid search/AdSense, AdWords, parked domains
Joint development
Intellectual property licensing
Contractor agreements
Content licensing (in and out)
Domain development and optimization
Social networking agreements
Hosting and bandwidth agreements
Website terms of service, terms of use, privacy policies, infringement/DMCA policies
Domain/URL purchase, sale and lease
EULAs (end user license agreements)