In an attempt to use up some miles before they expire, I'm starting to plan a trip that will involve (hopefully) a combination of award and non-award travel on 3-4 different airlines. Any ideas on planning this other than brute force searching? I remember seeing something a while back about a web site to help plan such trips, but I can't find a reference to it any more.

perhaps a few more details would be helpful.

If you're flying international, you're allowed 1 stopover on an award ticket.

Last summer we wanted to fly to Japan from NY on an award tix. UA allows you to stop somewhere, so we went JFK/BKK/NRT.We just as easily could have made that stop in SFO.

That doesn't really help, as there are no valid routings on any airline that would satisfy the stopover requirement (such as LHR-TFN-TLV or LHR-TLV-TFN). I expect to have to use the AA miles (60,000) for one part of the trip and BA miles (36,000) for the other. It might work to try some airline LHR-XXX-TLV-XXX-LHR and purchase the XXX-TFN-XXX R/T (where XXX is some airline's hub, like Madrid or Rome), but I don't think that's an optimal use of the miles.

http://www.awardplanner.com

Mileage expiration can usually be extended. You mentioned AA as one of the airlines. Any activity (including an iDine restaurant visit, for example) will extend all your AA miles for 3 more years.

[edit for typo]

Bingo! Thanks.

AA is easy. Our BA miles are the ones that expire next summer, and they don't seem to have as many earning opportunities...

BA is easier as any activity on your BA account (not only flight activity) will extend life of your account by 3 years. I'd consider
- changing earning preference on some of your hotel programs to ba miles and make a stay (almost all hotel programs will provide at least 500 ba miles for that)
- provide BA account number when renting a car (at least avis/hertz will give 500 miles for that)
- make a mileage transfer from any of your existing hotel/other accounts to BA account (i.e. for Marriott Rewards and Priority Club) you can exchange 10,000 points for 2,500 miles
- purchase something which qualify for points (see BA Executive club forum... although slim chance if you are not UK based)
- if you are in US, sign for BA signature card and get 15,000 miles with the first purchase
- if you fly BA, buy something in on-board duty free
- if you will be in UK, use travelex currency exchange, rent phone from worldroam or use BCP or BA Express parking
- subscribe for business traveler magazine (400 miles for 1 year subscription) - only as a last resort or if you really like the magazine as it is almost $180

many other options is also available