One problem: good international communication infrastructure. Speedy DSL, even business ones are not that good. On the best of days, it delivers what you paid for it (2mbit or 3 mbit). On a mediocre day, it's fast connecting to local servers, but not so good to overseas/western servers.
But to answer your question:
- programming services for websites (forms, apps, etc)
- tech support
- programming services for office apps (ie timesheets, databases, etc)