Personally, if I had $20K free to invest, I would throw half of the money into Ameritrade for 10K starwood points and use a credit card to purchase US savings bonds with the other $10K. If you use a Starwood Amex card to purchase the bonds, you will get 20,000 Starwood points with these two transactions (10K with Ameritrade and 10K with your Starwood Amex). This is in addition to any sign-up bonuses (currently 4k) you get for getting the Starwood card (free in the first year). If you look at the www.spg.com site, you will see that 20,000 Starpoints equals 25,000 miles in most airline programs (except United). And many here would argue that Starpoints are more valuable when used within the Starwood hotel program.

All this assumes you (1) don't have liquidity needs within six months, since you can't redeem the savings bonds until after one year, and (2) want to be invested in the capital markets since Ameritrade offers a pretty lousy interest rate on cash balances.

With respect to investing, if the $20K represents your current total savings, then a more diverse asset allocation would be more appropriate (i.e., XX% savings bonds, XX% ameritrade/tdwaterhouse/another broker, XX% rainy day money market fund). A good option for a cash account would be ING Direct. A lot of folks will offer to refer you to ING. You will get a $25 account sign up bonus if you use their referral. However, if you go directly to the following link:

https://banking.ingdirect.com/saving...p?p=%99WSs%A8u

you will get a $50 sign up bonus. The usual 6 month holding period applies, but there is NO minimum deposit as far as I recall.

Another good cash account option would be Netbank, which should still have a promotion with Priority Club (Holiday Inn) that offers up to 10000 points (transferable into 2500 airline miles in A LOT of different programs) for a minimu $500 deposit and a six month holding period). Check pgary's excellent site for the latest on this promo.

What's great about ING and Netbank is that they offer some of the highest interest rates around. 2.2% for ING currently for a regular savings account. They don't offer paper statements though.

Finally, here's the link for the ameritrade/starwood promo

http://www.ameritrade.com/spg/