I made a post two days ago about the current airberlin promotion of free Silver status for joining their topbonus program. I am posting again because this really is an amazing deal.
The airberlin airline is in the OneWorld alliance, along with American Airlines, British Airways, and many others. Topbonus Silver has OneWorld Ruby status across the alliance.
If you're an infrequent flier but have a few trips coming up, this promotion saves you time and money. Saves time by using the first class checkin at the airport and early boarding, saves money by giving everyone on the same reservation one free checked bag.
This status is only good for four months but if you have travel coming up soon on AA, BA, or others, follow the instructions from my previous post to save some scratch.