The first credit card to ever feature a 100,000 mile signup bonus has just brought it back. For a limited time, through May 6, 2011, the British Airways Visa Signature card is offering up to 100,000 bonus BA miles, enough for 2 transatlantic roundtrip reward flights. You’ll receive 50,000 bonus BA miles after your first purchase, plus an additional 50,000 bonus BA miles after you spend $2,500 within the first 3 months of opening your account.

BA miles can also be spent on partner airlines including AA, Cathay Pacific, Finnair, Iberia, JAL, LAN, Hungarian Airlines, Mexicana, Qantas, Royal Jordanian Airlines and S7. The card does carry a $95 annual fee.

Standard features of the card include:

• No foreign currency transaction fees
• Earn 2.5 BA miles for every $1 spent on British Airways purchases
• Earn 1.25 BA miles for every $1 spent on all other purchases
• Earn a Travel Together Ticket (free companion award) after you’ve spent $30,000 in a year on the card

Edit May 6, 2011: This offer has now expired.

Edit May 16, 2011:While the offer for 100,000 BA miles has expired, you can read this post describing how you can get 50,000 BA miles with the Chase Sapphire Preferred card, with no annual fee for the first year.