The internet is abuzz with talk of Google's entry into the smartphone hardware market with the (codename) Nexus One, but that's not all the internet search giant has been spending its money on.

Google recently acquired mobile advertising company AdMod, and now speculation is growing that these two new ventures aren't so separate as they might initially appear. There's been a lot of talk about Google wanting to provide the HTC-built handset SIM-free, but smartphones are notoriously expensive when carriers aren't subsidising them.

It's therefore not at all impossible that Google is testing out a whole new way of providing affordable, feature rich handheld hardware by using mobile adverts to subsidise its handsets.

It's all just rumour at the moment, but the pieces fit together quite nicely given that Google has no apparent interest in joining the network carrier business. Time will tell.