Or, like when I interviewed once at a very large broadcasting org, they put you in a meeting room with a laptop (windows 7 which I never used before, bad keyboard, bad editor, no internet or reference), give you some half arsed questions and piss off for 30 minutes without you being able to ask what they actually want. Then 10 minutes later someone else comes in and asks you what the hell you're doing in that meeting room, you have no way to contact your interview partner, no idea where he went, they hassle you for about 10 minutes about it, and when your interviewer comes back you haven't been able to even get into the task, let alone write some code ...

Waste of time also, especially if you factor in a 2 hour commute each way.