Anyone tether their iphone to their lap top. If so any hiccups or does it work seamlessly?

I believe O2 absolutely pump you for data charges so I've never bothered.

I've been tethering via my N95 for several months on O2 and not had any extra charges (with an "unlimited" data bundle). No experience with an iPhone but if you can get it to connect OK I can't see how they'd know without using deep packet inspection. As long as you don't take the piss and download gigabytes of torrents I'd have thought you should be alright.

May be worth a read

http://www.engadget.com/2009/06/18/how-to-tether-your-iphone-running-os-3-0-without-jailbreaking/

I was actually looking at doing it legal. Be moving soon so will be having mobile internet and most places want £15+ for 3GB and noticed I can get it for £10 tethered with an iphone.

I've done it before, via the O2 bolt-on option.

It worked flawlessly on my old HP laptop, but I struggle to get it to work with the new Acer.
I think thats the laptop though, not a phone problem.
Anyhow, when it works, it works very well.