Ancient computers in use today

Technology and computing in particular has a rapid cycle of innovation and obsolescence. However in some cases old computing equipment remains in use decades after it went obsolete. PC World covers a few systems still in use including a warehouse inventory system still running on an Apple IIe, PDPs still in use by defence establishments and most amazingly an IBM 402 accounting machine from 1948 which is apparently still in use by a Texan chemical filter company. The IBM 1401 Restoration Project have more photos of the system in use, which is the last one in service in the world, and are trying to get it into a museum.

Many older computers are perfectly fine for certain tasks, though a 402 is probably pushing it a bit. However as one of the commenters in the PC World article says, at least the operators don't have to worry about malware and endless software updates.