After hearing a number of covers performed on instruments like the one below, I was wondering if someone has come up with a better name for this instrument than "PVC instrument".
They have been called Rimba tubes. Possibly from the term marimba.
Could have been a tuber, but I think there's something similar in existence...
I know it as the Thongophone because it's often played by hitting the pipes with a rubber thong (or flip-flop as it's known elsewhere :P) http://en.wikipedia.org/wiki/Thongophone
PVC marimba is the term I'm most familiar with for that type of instrument. It's better than the generic "PVC instrument", since it specifies that it's meant to be played percussively (and not a PVC wind instrument).
Blue Man Group has used custom-built percussion instruments of this type for years. You can research how Blue Man Group has invented and made use of these instruments. I do not know if they have specifically named some of them.
I found this Do-It-Yourself Guide to PVC Instruments page, with links to many other pages, at the website of the Zzounds music instrument retailer.
For clarity's sake, and since I hate acronyms, let me explain that "PVC" stands for "polyvinyl chloride" and refers to the synthetic chemical plastic polymer compound from which the pipes are made. Polyvinyl chloride pipes were originally developed for piping water through homes.