OK, nitpick time.

Since recent No Gnus apparently now wrap Face: headers with \n\t
instead of \n__ like it has been since Oort, I think this wrapping
looks much better:

Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAAGFBMVEX+2D5BBg
        HgZxmPJxLOSR6pNhrwgCBxFwYcdbd+AAACMklEQVR4nG3TwXIbIQwAUP8C4/
        FwbTGm17Ys5ppgNrk2BY2vydoh17hrl9+vJHadpO0e9UZCaMXClFKeBX+11t
        [.....]

Than (ugly!):

Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAAElBMVEVELCDTj4R/T0S0dGoa
        EQryvK8nnzuJAAACXElEQVR4nF2UzY7bMAyEWa17ryzorojJ3RKRu7HQC6gG3/9VOqMEi+4GMBD7
        M/9mKEsvRcoYMl6/8ywiYmZyhHKWscn2BqHWIkog2ykn3trOBWrT+0ZQ8GQLsgEtoKneh1onEFEm
        foGbdYIqpQDUBQQtSIupDO11RVStqLlYyD6PoZUA3aXKYD6/uc+ywHGK4q2YOvoM5u7XdrLl4wwN
        [.....]

Lines ending in column 68 in the first example look much better
than 84 in the second.  I arrived at 68 after playing around with a
few different values in the 70-75 range -- it would append the last
line to the second-to-last line in those cases.

Anyone willing to commit the attached patch?

-- 
    aaraines@pobox.com (Andrew A. Raines)