Yes, this is exactly what Armory does. It's why I made it. As far as I know, it's the only program out there that has a simple graphical interface for managing offline wallets, watching them using online wallets, and spending coins using USB keys. Your private keys never touch the internet, but you can still generate addresses online with no risk to your funds (only your privacy). Once you get past the long load times it is a phenomenal solution (and I'm working on the load-time thing for the next release).
Wow, I watched the presentation and I like what I see. Keep up the good work!
I'm still in the "I'm Scared" phase but will try it out in a month or so when I (hopefully) get my mining hardware and set everything up. And yes, I will make sure a donation finds its way towards the Armory developers, lol.
@Zangelbert
That's exactly what I'm talking about. Most of the replies in this thread present more or less complicated technical solutions to secure the wallet. However none of them (although Armory comes close) are ready as a mass-market solution. The convenience of an online wallet (like my online banking) is something we should strive to achieve, but it has its own drawbacks. Who is going to maintain the server? What if that server data gets hacked/deleted/confiscated?
So, how can we overcome those drawbacks?