I'm in Melbourne, Australia, working (contractor) on a project based out of Sydney, Australia, with team members working in Georgia (state, not country), Alabama, California and in the Philippines. In the past, I've worked (from New Zealand) for a company out of Finland, and (from Melbourne)for a couple of companies out of SF.

My main experience of remote work is that a 'normal' 8 hour day doesn't work - everyone needs to be a little flexible with their days and hours of work both for regularly scheduled standup meetings and for ad-hoc conversations with workmates. The oft-seen "US only" may be a timezone related concern.

I understand that international payments are seen as comparatively cumbersome, and (for employees, at least) the tax situation may well be more complicated.