A while back Javan shared with me his idea about a cuddle bed. At the time I think he just met a nice girl who he wanted to be extra close with in the in the bed, without having his arm fall asleep. The Cuddle Bed is basically a mattress with a hole in it so you can easily position your arm around your significant other. In addition to coming up with great ideas Javan takes amazing photos, check out his new photo blog.
I think you might also have to buy some specialized sheets for this bed too.
A while back GJ Echternkamp shared another wonderful idea for couples along the same lines I will be posting about this week (I need to get the graphic ready).