Connecting G1 to the Internet through a Windows PC?

[ydkz2004-g1]

What I am looking for is the opposite of “Connecting a Windows PC to the Internet through a G1 phone”.

Here is the specific situation:
From my office, which is inside a big building, 3G connectivity is poor. Therefore, the G1 phone cannot access the Internet through t-mobile.
There is 802.1b/g, but they are secured against alien devices, so the G1 is denied access.
On the other hand, I have Gigabit Ethernet to my PC. What I am looking for is some sort of proxy, NAT or Internet sharing software, connecting through USB or WIFI.

G1-->USB-->PC-->Internet
or
G1-->WIFI-->PC with WIFI card-->Internet

[kPkpkp]

G1 -> USB -> My Laptop -> Wired LAN -> Internet

I have the physical connection - just need the logical.

I assume will require an app or driver running on the both the PC and on the G1