I just use the same thing you do.... Tamrac bag... If im traveling on the bike, i have larger crown royal sachels (i dont know how to spell that.) That I will wrap one in the body, and one in the lens, then just carry it in my tank bag if in the motorcycle. As for around town; they make larger cargo type bags that dont go around the shoulder, they are quite spendy, we both need one of those...... but I have not purchased one yet. No real need too at this point. Since my largest lens has a case the size of my normal Tamrac bag, and it has a shoulder strap. So at this point im just carrying two things on my shoulder instead of 1 at the moment. BUt the crown royal bag trick is pretty cool
