Did you know in .Net strings are immutable? Neither did the guy at Google when he asked me to do some "in place" string fiddling algorithm or that guy at Amazon

Did you know in .Net strings are immutable? Neither did the guy at Google when he asked me to do some "in place" string fiddling algorithm or that guy at Amazon who wanted to reverse the strings in a sentence (yes there's a trick to that one found in some 80s programming book)