Wanted solution:
[internet]---[3G USB modem]---[Windows7]---[WLAN]
I have a Huawei E367 modem that is connected to a Win7 machine's USB port. This works alright. (except huawei's love for intermittent stops)
Now I want to share my internet connection from the 3G USB via WLAN.
On controlpanel->networkandinternet->networkconnections I see LAN, WLAN, bluetooth and 3G.
I can bridge LAN/WLAN but not anything 3G. (or bluetooth for that matter)
On 3G->properties->sharing I can set up a share of sorts but that is computer-to-computer and not a "normal" wlan so that is not usable for me for other reasons.
Is there a way around this (except buying a 3G router)? A setting I haven't found, a program that does it, updating to Win8, linix live CD or antyhing that doesn't involve placing the 3GUSBmodem a place the sun doesn't shine very close to the developers of the thing? The latter wouldn't solve my problem but would give me a temporary feeling of satisfaction.
Update Rereading this QA I see that the solution was a bit hard to find as a comment to an answer. I went with virtualrouter and it worked without a problem. It is F/OSS so please keep hacking.