I guess mine is 'custom'.

Its one of the first few proto macneil 22" frames, so it has no serial number.
The frame has been sandblasted and powdercoated recycling box blue.
I built it up myself with components I picked based on my riding style
(LHD cassette etc).
My stem has been milled/tapped to accept larger bolts for more bar clamping force.
My Bars are chopped to 23"
Seatpost cut.
Custom spoke/plate brake straddle cable to increase leverage.
Custom Delrin Grind plate on one pedal.