Sex Toy Solution: Handcuffs
If there's one thing that makes sex undesirable, it's always having to think up some imaginative thing to do. This is the biggest trick in my book: if you really want to be lazy in bed, then some dominant/submissiveIt role-playing is the best way to ensure that you can have a relaxing sex life. Of course, you must play the submissive. Integrating handcuffs into your sex play relieves you of all the responsibility of being creative in bed, and forces you into the lazy position you desire to be in (or whatever position he desires to put you in...whatever, you don't have to do anything in the end). One tip--make sure to put up a little struggle every now and then, or else he'll get bored and you won't get to do nothing anymore.
Personally, I prefer the nice cold metal of these Fetish Fantasy handcuffs ($12.99 at RomanticGifts.com). But I get into the whole submissive thing (almost to the point of being active if you can believe it!). If you think that metal is just a little too BDSM for your liking, you can give any of these a whirl, too: