Generally used to designate a poorly drawn smiley in MSN messenger that may or may not look like a fly. In reference to a Jack Handey Deep Thought that ended with "That alien!", but written in english shitty enough to make you invert singular and plural and put the letter D instead of the "th" sound.
MikeK: Mans! Loks at my nwew smilyeS!

D: Shoot!

MikeK: <shitty smiley>

D: whtat the fkucs is that supposeded to be?! it looks like a fruit flies or smomethinigs!11

MikeK: Dat Flies
by D June 1, 2004
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