Modding a bag: adding a strap

Has anyone had any experience modding their camera bag by adding an extra strap here or there?

I have a Lowepro Nova 2 (http://products.lowepr​o.com/product/Nova-2-AW,1973,20.htm), and I've found that it would be a ton more useful if it had some horizontal straps on the sides of the bag.

I recently bought a Sigma lens that came with a lens case. It has a vertical loop that you can loop into a belt or something. I'd like to attach it to my Nova 2 but there's no decent way to do it without a mod of some sort. Plus I find the small elastic mesh side pockets next to useless.

My idea is to sew on an adjustable plastic buckle strap just above the mesh pocket and below the shoulder strap. What do you guys think is the best way to do this? I'm afraid it might be a tough to sew it on properly through the thick material and padding.

Are there any other useful mods you guys have pulled off?

New lens .............. New bag

Only makes sense. Just get one big enough for another lens or two this time.

When I don't need to carry everything I own, I use a Nova 5 bag. I have added a horizontal strap to the back so it can be clipped safely to the telescopic handle on my suitcase. I used a couple of straps that fell off a supermarket trolley. No, really! They were actually lying on the tarmac in the car park! It would have been a shame to waste them*.

I've also sewn on a couple of smaller straps for a monopod . These are attached at either end of the top flap. These I took off my Vertex backpack as I have no intention of ever trusting the stupid glide lock design after one fell off a brand new bag. Loweprow had a brain meltdown when they dreamt them up.

*I have used these trolley straps before; as battery tie down straps on a boat. Thankyou Mr Tesco.

Richard