Yes, You can use your Tablet to access the internet on a desktop/laptop which has no access to it.
For Example,
Tablet:============USBCORD============PC
In the tablets wifi options, there should be an option to enable wifi tethering. I'm pretty sure the Tablet will lose Internet functionality while it is active, but the PC should be able to reach a new access point then. After you stop, the tablet gets its functionality again. (may be wrong with the losing internet on the tablet thing, but it shouldn't matter.)
Hope it helps!