I personally also prefer to say "free em ci boot".
MC is a shortcut for a combined noun, so in my logic every one of those two letters are there for a single noun ("Memory" and "Card" ^^ ) and it is no "Mc" like from "McDoof"/McDonalds.
...or of course, like bfoos said.
PS2 V7/DMS3 V2 (FW:2.4b7); Seagate Baracuda 200GB
PS2 V7/CC1.0 (FW:34 hacked v2 BM:2.1.6); Maxtor DiamondMAX9 PLUS 160GB
PS2 SCPH-30004R; NoMod+NoLaser
3xSony MC 8MB
MAX/Datel 16MB with Boot-CD
Custom FMCB 1.8b+ Beta-Build, my AIO 0.5, Sony&xRhino-Linux