How much gear are we talking here, Doc?
I know I am on the light side compared to many TMIPers, but I was able to construct a pretty good camera gear case for my stuff out of a rolling pilot's case from WalMart, and some dense furniture-grade foam rubber from a local supplier. I had the foam cut to fit snugly into the case, then cut custom slots for my gear into the foam. I am able to fit 1 SLR body, a bridge camera, 3 lenses, 2 flashes, multiple batteries, memory cards, and other small accessories, in a single case that is convenient and easy to manage, but also doesn't look anything like a camera case. It also has a slot for my laptop. I further modified the original case by adding U-bolts to the top so I could clip the shoulder strap from my Canon camera bag onto it.
Cost of the case was about $40. Cost of the foam was about $15. Cost of the U-bolts, nuts, and lock washers was about $5. Total cost of the project was about $60.
The only bad part is that since I could not get sectioned foam like Pelican cases use (unless I wanted to pay the premium for a Pelican insert), I will have to replace the foam periodically as my gear changes. I have mitigated this slightly by making several of the cut-outs basic rectangles that can accept a variety of gear, but every so often I'll have to buy another $15 worth of foam and cut it out. In fact, since I just got a new camera body with battery grip last week, I'll have to get a new piece of foam for the bag before my next trip, whenever that might be.