I also forgot to mention, another great way to gain confidence in new areas is to experiment and R&D in your own time. Pick projects that will leave you with a

I also forgot to mention, another great way to gain confidence in new areas is to experiment and R&D in your own time. Pick projects that will leave you with a clearly demonstrable experience of a marketable technology (eg Node.JS is cool but difficult to find wide market interest at this time). But only do this if you have time between gigs - always take a gig over a project because you will always gain some kind of experience from any gig, in addition to getting paid.