Good going! I paid off my first student loan which gave me an extra $300 a month. I thought I was rolling in money, until I have a bunch of kids :)
If I'm just limited to backpacking gear it would be a cuben rig, shelter/pack
Otherwise if I had $1400 extra a month I would invest in a secure financial future (not in stocks right now). Save in the bank or otherwise invest it. I would love to buy a patch of land next to a big NP, lake, or beach. Any one of them would appreciate in value while providing recreation for me.
If you don't need the financial security or gear, perhaps donate a portion to charity or an organization devoted to perserving the earth we love to walk on.
…. or maybe a big chrome motorcycle.
hmmmm, that's a big delima. Good thing I'm broke :)
Let us know what you go with.