Longest without any breaks would be suomynona. Ignoring breaks ishi & jarmund would be the at the top end, though putting exact dates on it is proving to be rather difficult. (sometime in 07)
hanz0, siku & avwave pre-date me, though from what I can gather we're all from the same year. (staff since 08)
So yeah, in terms of total time serving without any breaks suo is the winner.
<Erf> SkulFuk: gf just made a toilet sniffing joke at me
<Erf> i think
<Erf> i think i hate you