If there was a way you could leave a tip for someone without having to actually part with the money, would you tip more?
Well, I'm working for Amazon.com by putting banners on my site. They will give me a small % (very small) of what anyone spends who visits their site via one of my links or banners.
So, if you plan on buying something from Amazon.com, would you consider going there via one of my links?
Proceeds will go towards...well...either gas or grocery money; whichever is in greater need at the time :)