Mirabilis ICQ is a very popular chat program. Thanks to a neat program called ICQ Plus, ICQ is now skinnable. There are some Mortal Kombat skins available for it (both based off the MK movie). Personally, I don't like using MK skins with my ICQ as it makes the letters kind of hard to read. But if you're a die-hard MK fan you'll want to use these skins anyway, or at least have them.
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