When I'm in SF one of my favorite places to be is at one of those little tables in front of Orphan Andy's where the Market St streetcar turnaround happens. There's a live cam that points at it, it's very rainy there right now and it's creating a great ambience for my little PNW home office. Think I need to invest in a wall-sized TV for this sort of thing.
@pieist
One of the niftiest things I've seen is someone mounting large wide-screen displays on the wall vertically, and then dressing them out to look like windows. Not quite a holodeck but it did give an impression of being... well, wherever you wanted to be (especially with the appropriate ambient soundtrack). Maybe worth considering?
I may at some point be moving to a windowless basement office; if that happens I definitely plan to do this (including a feed from an outside mike and camera.)