This is more of a common sense thing, but I'm posting it in the exploits section because it is clearly not intended and may help some people out. Anyways here's what you do
1. Find a trusted friend who has paypal attached to the RMAH
2. Have them post a junk item for however much money you want to convert
3. Buy out the junk item with your blizzard bucks
4. Have them transfer you the funds over paypal
5. Profit
This is useful for those of us who are unable to cash out in the RMAH for various reason (not having a phone plan compatible with the mobile alert system, for example).