I've made a recent move from full-time information technology architect for an e-commerce solutions provider back to the role I played for the seven years prior to joining that company in 2007: technology consultant. Probably I'll be asked by clients to perform duties that on the surface seem pretty similar to those I was doing for my full-time employer; however, appearance can be deceiving. A lot of what you end up doing in a full-time gig, especially if you're in a senior role, only marginally relates to your "primary" responsibilities. These "secondary" duties often consume a large chunk of the day (project management, procurement of hardware, software, etc.). A consultant, on the other hand, is often hired to perform a very specific role for a very specific time period. Sometimes organizations bring on consultants for an unspecified period of time to essentially fill a full-time position, but I'll be specifically shying away from those engagements this go-round.
I'm not suggesting that one role is better than the other. Both clearly have their pros and cons. But I'm ready to focus more on the task(s) I feel I'm good at and that I like doing and consulting gives me what I feel is the best opportunity to do that. Or to go broke trying. :-) Of course, it'll also land me in places I'd rather not be (but I'll ensure that this only happens for short periods of time by keeping the contract lengths short). With consulting, I have to keep on my toes over a broad spectrum of technologies so that I can be 'the expert' on short notice. I like that. I also have to deal with the uncertainty of (un)employment from time to time and the possibility of significant travel, which I don't like so much. Still, on balance, the siren song of consulting finally won out, at least until I can find out what I really want to do when I grow up. :-)
If I have my druthers, I'll be focusing on large scale web capacity, scalability and concurrency challenges and resulting solutions for clients. That's where my passions are these days and will be how I orient my marketing message to potential clients. But whatever the gig, I'll do my best to make the most of each engagement, always on the look-out for that next special domain and/or organization that I might want to stick around with on a more permanent basis.