Just got a Nikon D40

[flatflip]

I have really been wanting a Nikon SB600 flash for my D5000 (and hope to upgrade to a D7000). I found one on craigslist last night in a camera kit and picked it up today. Looking for hidden gems of tips and tricks (advice) for the equipment in my kit. Thanks, Mick

Lowepro backpack
Nikon D40
Nikon 18-55 not VR
Sigma DG 70-300 4-5.6
Nikon SB600 flash
Nikon ML-L3 remote