from select cities on east coast, and you can use them in combo deals.

http://www.spiritair.com/welcome.aspx?pg=salesinformation&number=78

Anyway, it's more than halfway to Bonaire. Good only for Nov and Dec, very select dates, but I went there and got all the way to purchase on a week r/t ticket, just to see if it was all sold out and it wasn't. Sign up for the travelzoo.com weekly top 20, and you just never know what might come up. Good for purchase thru Nov 7th. Hope this helps someone!