RE: For those of you with big babies...
If he has adequate neck control, you might try a backpack carrier. But if it's the contact he wants, then that may not cut it.
I have a friend whose baby was 24 pounds at 6 months. Now at 14 months, he's only around 26 pounds. He just started leveling off. Once they get mobile, they don't gain weight nearly as quickly.
When Sarah got too heavy for me in the Bjorn (around 20 pounds), I started using a sling as a hip carrier. I cna carry her like that for ages. I think it might be a little better than the Hip Hammock, personally, because part of their weight is carried by the fabric of the sling and more evenly distributed across your back and shoulders rather than being in a small strap which digs in at your shoulder. But I have never actually used a Hip Hammock, so that is only a guess. It's worth a try. You can get used slings off eBay pretty cheaply.
Hang in there!
Beth, mom to older DD (8/01) and younger DD (10/06) and always missing Leah (4/22 - 5/1/05)