Apparently HBO will be offering its shows via Vodafone's 3G mobile phones in Europe. The options (Sex and the City, Six Feet Under, Curb Your Enthusiasm) seem to be shows that have finished their run, so neither Rome nor Deadwood is available, but i4u.com has quite a list of other channels (including MTV, Discovery, Fox, and Eurosport) which are carried via Vodafone in the UK and New Zealand.
It's interesting that one of the side-effects of the convergence of TV and electronic media is the divergence of ways in which people consume that media. I suspect that while it's easier to repurpose existing content for phones and portable video players like the video iPod, the not-too-distant future will see more content being created specifically for mobile platforms. (Whether that content will have to sell itself by association with a pre-existing brand, like the 24 and Lost mobisodes have, is quite another question.)