10 years ago I wrote a sales system in Perl with a couple of friends. We charged something like US$750 (it was really simple: uses a hash instead of a database). It is still going strong (no bugs reported) and about US$500.000 has been sold with it. That's what I call ROI and stability!
Totally off topic, but I really dislike how ruby (and I guess others?) has popularized the word hash to mean a hash table. I stare at that sentence for a good two minutes thinking "how does someone use md5/sha etc instead of a database???" before I realized what was meant. There are plenty of good (and well known) unambiguous names for this data structure that I really don't understand why it needs to be given a name that's in common use to refer to something different (and only kind-of related really). Some alternative names that have been in common use since the dawn of time are hash table, hash map, map, dictionary or associative array.
