Warehouse 13!!!!! great show, with many references to comics, games and other nerd things, and great steam punk equipment (what else do i have to say, watch it)
there is also two cross episodes with Eureka, but its totally different.

Chuck, ok not scifi, but action/spy/comedy, i love it

Torchwood, if you like Dr. Who you will love it, though the first season is shit, but the third one is the best mini-season i've ever seen

V, its a remake of an old show, sometime to much USAUSAUSA (sorry guys) for me but still good

Flash Gordon 2007, yes they made a remake, can't recommend it (also got canceled after one season), but if you can't find any new stuff....

Fringe, fbi agent thingy with mysterious parallel worlds

Sanctuary, about 'monsters' and other stuff, with amanda tapping (stargate sg1)

Misfits, some teenagers get some 'super' powers, not what you expect

Primeval, dinosaur from the past etc

Hereos, humans with super powers, has some good and some bad seasons