If women thought more like men, the Cleavage Caddy should have been a huge hit. A secret purse designed to clamp under a woman's bra, it gives you a literal rack to wear over your rack.
Alas, it wasn't a hit (at least, I don't think I ever knew any woman who owned one). First sold back in 2008, I haven't seen much about this clever (albeit uncomfortable-looking) little line of pockets for gadgets since then. The website's still alive, but there seems to be no activity. Seriously, though, why wouldn't women want one?
The Cleavage Caddy anchors to the bra using an elastic strap with a snap at the end. Pockets are lined up right against your breasts, so you can stuff them with towels and toilet paper if you're trying to fake a bigger cup size. What else can you put in those slots under your shirts? A whole lot, from keys to wallets to iPods to cellphones to laptops (okay, I was kidding about the laptop part - unless you buy the super-duper-extra-large).
With all those oddly-shaped items you can put there, of course, your chest will probably look more like a box than big, bouncy balls. Still, the convenience of having all that crap in one accessible place (all you have to do is dip under your shirt to get them) sounds worth it. Mmmm...okay, maybe if you're a guy.
Not sure about current availability, but Cleavage Caddies are listed at $30 apiece. If guys wore bras, I'd have bought three of these already.