nice... you can eliminate those backslashes by using the q operator. It allows you to choose your string delimiters, like so:

print unpack(u,q/92G5S="!!;F]T:&5R(%!E<FP@($AA8VME<@``/);
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Or since this is obfu, pick an unusual char for a delimiter, perhaps 'u':

print unpack(u,q u92G5S="!!;F]T:&5R(%!E<FP@($AA8VME<@``u);
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even better, how about ',':

print unpack(u,q,92G5S="!!;F]T:&5R(%!E<FP@($AA8VME<@``,);
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This lets us obfu it further...

print unpack u,(q,u,,q,92G5S="!!;F]T:&5R(%!E<FP@($AA8VME<@``,);
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figuring that one out is left as an excercise to the reader...

Read more about it at perlop.

-Blake