Defendant to plaintiff: How much is that in Linden dollars?

As MMORPGs continue to grow in popularity and economic significance, so do the legal issues surrounding acts undertaken in virtual worlds.  Already hot topics:

• copyright infringement for unauthorized duplication and sale of in-game objects
  
• trademark infringement for unauthorized in-game use of real world marks
  

By the way, if you haven't already seen this, Second Life was hacked this week:

[S]ome of the unencrypted customer information stored in the database was compromised, potentially including Second Life account names, real life names and contact information, along with encrypted account passwords and encrypted payment information.

To quote Digg user KodeK:  "Second identity theft? :-)"