New Bike?

I had a thought today ....... I was thinking that I want a new fixie for next summer. I love the one I have now, It is a vintage 1975 Motobeacane Mirage. The frame and the forks are the only things that are original. I have white Weinmenn wheels, with origin 8 hubs, new bottom bracket, riser handle bars, and some other things. I love the bike because I got it for 30 bucks and I built it all myself. But I am think that it is time to move on to bigger and better things. If I sell it I think that I can get 3 or 4 hundred for her. (hopefully 400) I definatly want to build my next one too so I think that I want to get this frame ...... (I can't get a picture of it but here is the link) Alien Bikes I like the lines and how the down tube is curved to fit a back wheel in there. I think this is the one I want to build next.