You can go to your local bike shop and get 2 bike hooks to hold a bike up with. They are large hooks that will screw into the beam and when the kids are away you take down the bike and hook up your wife.

Another Idea is a ceiling Fan. When the kids are away at grandmas. Turn off the power. And take a close look at the fan they are usualy sturdy and are made to support the waight of the guy instaling it. You might be able to suspend your wife from the fan. and if she has been realy naughty you can turn it on and she can spin while you whip her.