Depends on where you are going from and what time of day you want to travel and what the prices include. Put your requirements in skyscanner.net and have a look at times and prices. Most likely your options will be Easyjet plus maybe Ryanair.
That is so sweet of you Mazie. I took myself off AB for reasons due to another section. However, I came back to the bits that are enjoyable and will not go where angels fear to tread. Apologies to Miller for chatting in this thread.
got anything against Tegel? Anyway, Easyjet go to Schoenefeld, and they're probably the cheapest. The flight's less than two hours so you probably don't have to worry too much about seat comfort or meal quality.