I mean the money/effort spent on this litigation.

It seems to me that HP would be better off sinking this money into contributions to PostgreSQL / EnterpriseDB; it already offers a ton of Oracle compatibility, and runs on HP-UX: http://enterprisedb.com/products-services-training/products/postgres-plus-advanced-server/advanced-server-oracle-features

I know of one for Mac OS:
http://github.com/mxcl/homebrew/
It would probably not be much of a challenge to make that work on a Linux machine. That and a Linux tool for this probably already exists.

I don't remember that.