Here is what I have with me nearly every minute of every day:
As of February 2011 – I’m shooting with a Canon 7d
Canon Xsi (450d)
Canon 28-135mm 3.5-5.6 IS
Canon 50mm 1.8
Canon 70-200mm L 2.8
Sigma 10-20mm 4-5.6
Sigma 19-55 2.5-4

All Carried in a LowePro Backpack

Software:
Photoshop CS2
Photomatix

Canon AE-1