Businesses in Second Life
From Sl Wiki
Real World (or "RL" - Real Life) businesses started to appear in Second Life around mid-2006.
While there may be many reasons for their involvement, it is certainly true that one driver for the first wave was PR. These first arrivals sparked off (or rode the tide of) a media frenzy, that has resulted in a huge increase in the number of user accounts, and more importantly, online users.
The following is a (non-exhaustive) list as at mid-Jan, 2007.