A recent WSJ article offered some tips on high-deductiible/HSA plans:

Unfortunately, many workers apparently are choosing high-deductible plans without funding HSAs. Some 40% of HSA-eligible group-plan users haven't opened or contributed to an account, according to an analysis in 2007 by UnitedHealth Group. That means some employees are leaving themselves open to large medical bills they may have no other means to pay.

Maximum annual contribution limits for HSAs currently are $2,900 for individuals and $5,800 for a family. Individuals age 55 and up can make additional "catch-up" contributions. (Whether contributions are pre-tax or after-tax depends on how the plans are set up, the Internal Revenue Service says.)