You most certainly can. I use my G1 to tether wirelessly to my laptop and I can host up to 5 computers as a WiFi Hotspot. I use the WOW Mobile service sponsered by T-Mobile. They offer true unlimited everything including data with no cap for $89.99/month, BUT, Refer 3 People As Customers And Your Service Is FREE! Follow the link in my sig to learn more..

So I guess u can only use you g1 as a modem if you root the phone ??

i use tether wifi and its great

This sucks I don't get it. Click where? I want my phone to give my pc internet. Help
Mozilla/5.0 (Linux; U; Android 1.5; en-us; T-Mobile G1 Build/CRC1) AppleWebKit/528.5+ (KHTML, like Gecko) Version/3.1.2 Mobile Safari/525.20.1

As far as I know you can only do it as Root currently. Hoping for something not-so drastic considering the only thing you gain from Rooting your phone is the POSSIBILITY of screwing something up or "quicker" access to stuff I will be patient for.

wifi tether for root users. Google it and you should be good to go.

Thanks for the info.

i dont get it... is htis free?

Hrm, I found something on this site:

Tetherbot

Installation

Read the bit above about no warranty again. This shouldn't damage your phone, but if it does, it's your own fault!

* Install the app on your android phone, by clicking here (from your phone browser of course)
You might have to change your settings to permit apps that don't come from the Google Market by going to your home screen and choosing MENU > Settings > Applications > Unknown Sources.
* Turn USB debugging on on your phone
On your G1 go to the home screen, press MENU > Settings > Applications > Development, then enable USB debugging.
* Follow the instructions here to install the Android driver - you'll need to do this on Windows & Linux but apparently not on the Mac.
* Download and install the Android SDK for your computer platform. Alternatively if you are on Windows and don't want a 100 meg download, just get the ADB utility from here
* Plug your phone into your computer

Using the Socks Proxy

The SOCKS proxy will let you connect things like firefox to the internet

* Choose Tetherbot from your phone's menu
* Press the "Start Socks" button on your phone
* Move to the directory that has the adb utility, using inside the Sdk Tools folder and run

Windows: adb forward tcp:1080 tcp:1080
Linux/Mac: ./adb forward tcp:1080 tcp:1080

* Now you should have a socks proxy running on port 1080 that you can use to configure firefox
* Set your firefox proxy : Options > Advanced > Network > Manual Proxy Configuration

Socks Proxy: localhost
Port: 1080

Leave the others blank
* Remember to disable your proxy settings in firefox if you want to stop using your phone.

Using the Port Bouncer

The port bouncer will let you connect to a single port on a remote host. This works well if you need to establish an SSH tunnel to your home machine.

This should work for TCP only vpns (openvpn can be configured in this mode) but it wont work for Microsoft PPTP (because it's GRE based) or most typical openvpn setups (because they are UDP based).

* Choose Tetherbot from your phone's menu
* Enter the hostname of the server you wish to connect to on your phone
* Enter the port you wish to use
* Press the "Start Tunnel" button on your phone
* Move to the directory that has the adb utility, using inside the Sdk Tools folder and run

Windows: adb forward tcp:4444 localabstract:Tunnel
Linux/Mac: ./adb forward tcp:4444 localabstract:Tunnel

* Now you should have a tunnel connecting from port 4444 on your local host to the port on the host of your choice
* To establish an ssh connection, type something like

ssh -p 4444 user@localhost

and you should be routed through to the server in question

It is possible to teather the G1 or use it as a modem?