http://skyrim.nexusmods.com/downloads/file.php?id=9504
Go to your favorite city / house / dungeon / whatever with your favorite followers and tell all of them "we'll stay here awhile" and then just leave them in place. Requires using a multi-follower mod but that's a not bad thing in my view.

No worries, all in good fun heh.
Yeah, multi-follower mod is pretty much the only way to do it. You can't order a follower to wait or relax in a specific location unless they are actively following you; in order to get more than one to do it they all have to be actively following, which is impossible without a mod for it.
It's sort of possible without mods for two followers, but only by taking one of them to where the other goes when dismissed and telling him/her to wait there. For instance if one of the two is also your spouse you can tell the second one to wait in the house where you and your spouse live. The spouse will be there anyway. But that's about it. And if you decide you want the one who lives there anyway on an adventure you'll have to dismiss the other and he/she will leave so it really only works if you want to have both of them waiting in the same convenient spot while you go off alone for a while.
And just telling a follower to wait somewhere may not work with the ones who get "bored" and leave your service on their own if you leave them waiting too long. Marcurio did that to me once, the little snot... OTOH he *did* warn me not to leave him waiting too long.

Incidentally the Followers Can Relax mod seemed to do away with that last problem, as long as I told him just to chill wherever we were he would find something to do and not get bored and leave on his own if I was otherwise occupied for a long time.