My wife's HSA is at
http://hsaadministrators.info/. The website has a section dedicated to HSA education that can give you a lot of good information.
Here's what we are doing with our HSA:
-Investing in 3 Vanguard Admiral Shares index funds for an asset allocation of 90% stocks and 10% bonds
-Pay for all qualified medical expenses out of pocket and save/scan our receipts for future reimbursement (most likely reimbursement in retirement 20+ years from now)
-Basically using this for another retirement account that will help us save big on medical expenses in retirement
HSA Administrators charges an annual fee of $45.