I finally bit the bullet and paid for a fixed sprocket and lockring for my old motobecane bike.  I bought them at Stevens and they were about 33 bucks together, with tax.  This puts the total cost of the project at 315 dollars, which is more than I expected, but I am happy with what I have.  I decided on the fixed gear partly because I’ve never had one before, partly to keep the very simple look of the bike, and partly because it was such an easy way to add some stopping capabilaty to te bike.  I thought about brake calipers but they would have ruined the look.  I still want to try a coaster brake and perhaps an internaly geard transmission hub.  Also, the seat on the bike right now is from an old mountain bike and looks rediculous, I am still trying to repair the old seat.  Those changes will come later, for now the bike is amazing.  It looks sleek and rides smooth, and it will continue racking up miles on the clovis bike trails.  I will post more pictures soon.