Most travelers participate heavily in the frequent flyer program attached to the airline they fly the most, and that’s it. And for the most part that makes sense. First, because you want to earn enough miles for an award ticket before spreading yourself thin elsewhere. Second, because it’s the easiest thing to understand. And third, because if you’re flying enough to earn elite status the benefits of that status (upgrades!) are usually strongest with the airline connect to that program.

But not everyone flies enough to earn status on their home program. Sometimes other partner programs with lower qualification thresholds would allow someone to earn status, when they wouldn’t crediting miles to the program of the airline they fly. [In one example, say you’re based in Los Angeles and fly both American and Delta a lot but don’t make status — if you could combine the flying in a single program for status you might earn status. Enter Alaska Airlines Mileage Plan, which partners with both Delta and American.]

And sometimes the benefits of another program are just too compelling.

If you are a 50,000 mile flyer with US Airways, Continental, or United you earn mid-tier status with those programs. And while you might get upgrades (and with Continental and United status flying on United, access to Economy Plus seats. Technically this benefit is a few months away for Continental elites, but it’s coming).

But you don’t get lounge access when traveling domestically. On the other hand, partner Star Alliance Gold members have access to lounges — including Continental, United, and US Airways lounges — when flying purely domestic itineraries in the United States.

And the award charts of some of those partners can be quite attractive. Especially compared to United, who has a nasty habit of blocking its members from redeeming for awards actually being offered by its partners.

While plenty of readers have heard me sing the praises of the bmi Diamond Club — with its reasonable elite status requalification levels (it takes 55,000 miles to earn Gold the first year, but just 38,000 to requalify), its generous bonuses for paid premium class tickets, and its cash and points award chart that leverages the miles you have, I haven’t often taken a close look at some of the other hidden values in the Star Alliance partnership. (I also like bmi for double-dipping with Hilton, since you earn 1000 miles per night up to 3000 miles.)

So I will briefly focus on three different Star Alliance partner airlines:

Air Canada Aeroplan requires only 35,000 flown miles for Star Alliance Gold status. While Air Canada itself has some fares that do not earn full qualifying miles, if you credit your United, Continental or US Airways flights to Air Canada all paid fares earn full qualifying mileage.

Aeroplan is an American Express transfer partner, and points post from Amex to Aeroplan instantly. There are some amazing awards, like first class from the US to South Asia for 120,000 miles (as far south as Singapre — Malaysia and Indonesia are more expensive). And their routing rules are exceptionally generous: routings from the US to Australia via Asia (not permitted by United), no additional miles to cross the Atlantic on awards between the US and Asia, in fact those awards let you route via the Atlantic one way and the Pacific the other. And they permit two stopovers in addition to destination on an international award (United, US Airways, and Continental only permit one).

Downside is that you have to have at least one transaction every 12 months to extend the validity of your account, and miles expire after 7 years regardless of activity level. There’s no way to extend. For me not a big deal, I use my miles. But you can’t just let them sit with Aeroplan forever.

I explained in some detail in December, 2008 why Aeroplan is one of my favorite frequent flyer programs.

Turkish Miles & Smiles requires 40,000 miles in 12 months to make Star Alliance Gold. That status is valid for 2 years. And — as long as you don’t reside in Turkey — requalifying only takes 25.000 status miles in the first year or 37.500 status miles over two years. (Note that while all United and Continental paid fares earn 100% flown miles for qualification, not all other partners’ discounted fares do — including US Airways.)

While some awards, especially first class awards, tend to be expensive there are also some amazing award values. Take for instance: Business class from North America to Israel and the Middle East is 90,000 miles (compare to 120,000 with US Airways). Business class between North America and India is 100,000 miles (compare to 120,000 miles with Continental).

You can top off your Turkish account with mileage transfers from Hyatt, you can double dip with Hilton, and credit your Avis, Budget, or Hertz rentals with them.

Asiana Club is great for earning Star Alliance Gold status and great for credit card spend.

Star Gold is earned after flying 40,000 qualifying miles within two years, and status lasts for two years. If you earn the status quickly enough, it can actually last for a full four years before dropping down and having to requalify again. Not all fares earn full mileage, however.

Since they have a distance-based award chart, award routings really aren’t an issue. You’re permitted four stopovers (two in each direction) in addition to your destination.

Awards can pricey for greater distance travel in premium classes, but flights totaling 10,000 miles or less are 80,000 miles in business class. That covers much of the East Coast of the US to Near Europe. (Compare to 100,000 miles with US Airways or 105,000 with Continental and United.)

And Asiana miles are exceptionally easy to earn for residents of the U.S.: the Bank of America-issued Asiana American Express earns two miles per dollar spent on all purchases (Update: Commenter Mordy points out that Bank of America now issues this card as a Visa!). That means an award ticket to Europe in business class for $40,000 in spend, compared to $105,000 in spend with the United Visa.

Like Air Canada Aeroplan, Asiana miles expire after 7 years (5 years if you aren’t elite). So you use ’em or lose ’em, this isn’t a program in which to save for retirement.

I described the hidden value of Asiana Club in greater detail back in July.

Playing with partners isnt’ for everyone, but if your reward goals match their award charts, or your travel patterns mean you could earn a higher level of status with them than with your ‘home’ carrier, they’re something to consider.