Re: List of supported channels/services
Roku has all of the terrestrial UK catch-up services (BBC iPlayer, ITV Player, All4, Demand 5).
You do need to register an account with Roku and give them a payment method such as PayPal (Apple and Amazon ask for this too, BTW). You can PIN-protect your account to avoid unauthorised app/channel purchases (a small number in the Roku "store" are paid-for). Other channels are "free" in the Roku store, but some are linked to Web video services where you need an account (eg Dramafever, Crunchyroll), and sometimes need to pay for a "Premium" account with the service, to get HD, no ads, etc.
In short: you don't have to buy anything through the Roku store, and if you're canny, you can avoid it entirely (if you only want the UK TV catch-ups, you're sorted).
One more suggestion: if you have an iDevice and want to "cast" Web video from sites/services with no Roku channel, check out "Video & TV Cast for Roku" in the Apple App Store (and its matching Roku channel). Seems to work well so far.
Biting the hand that feeds IT
