I use hash functions to generate a synthetic key; some people might call it a surrogate key, but I believe the proper phrase is synthetic. I currently use

keyField = CHECKSUM( HASHBYTES(‘MD5’, @VARCHAR(8000)) ) as a deterministic function that produces a INT key for data warehousing work.

I’m not in the position right now (due to work load) to test this out, but it will go into the investigate list for when my workload is lessened.