In my current incarnation as "pocket protector man," we work on both UNIX and WIN32 machines. Sometimes it's handy to be able to convert all the backslashes to forward slashes, and reverse. The first regex does the former, the second the latter.
I know how to change the delimiter, I just like the way it looks the way it is, sortof minimalistic. Of course this has probably been posted here before, but since I'm new to Perl (reletively speaking) I think it's pretty cool.