Been a home worker for 10 years now, VPN client on laptop so I can access all the file shares, all of the corporate apps and the usual email etc. What makes a great difference is having an IM client that will do voice, video and desktop sharing along with a voice over IP client thats setup with a normal phone number and can be setup with call routing rules to follow me about. IPass so I can access wi-fi hotspots when I’m out and about along with a 3G card if all of that fails. Then if I have not got my laptop handy there is web access to Outlook and the Blackberry.
Agree with the comments about it getting lonely sometimes and you have to set yourself some rules for example start and finish times otherwise the day just gets longer and longer. But the flexibility it gives and being removed completely from the usual office carp is well worth it, when you do go into the office it is for a specific reason and you can plan a very productive day.
Oh and the fact that it is a decent pay boost not having a commute every day.
Other big advantage is being able to get mid-week rides in at lunchtimes so you get some daylight mid-winter riding.