The newer Fenix 1AA lights are 123A wide to maintain LEGO-ability between the L and P series. To get a skinny 1AA Fenix you have to go back to their Luxeon lights - L1P, L1S, Civictor V1.
EDIT
For a small single AA light look at Jetbeam CLE or Dexlight X.V.
If you want a clicky the MTE C2 5-Mode SSC is thin but long.
Did you ever consider an AAA sized light?
EDIT EDIT
Jetbeam is releasing new versions of their lights with better quality control.