Aegean Airlines just recently joined the Star Alliance, and they have the lowest Star Alliance Gold level qualification tier, at a measly 20,000 status miles to qualify. As a Star Alliance Gold member you get access to all Star Alliance Gold lounges whenever traveling, even on a domestic ticket. A lot of Continental, United, and US Airways elite members will credit excess miles to a foreign Star Alliance airline to gain lounge access on all itineraries, even domestic ones.
Aegean Airlines is even offering 1,000 status miles to new members, meaning you only need 19,000 more miles to qualify.
It’s worth paying close attention to their mileage earning chart, as not all fare buckets qualify for full mileage. For example, while first class on United accrues 300% mileage through Aegean, some discounted economy class buckets (W class and below) only accrue 50% mileage. On US Airways and Continental, however, all fare classes count for a minimum of 100% mileage credit.
(Tip of the hat to Musings of the Global Traveller)