I was wondering...are you sharing your photos on some free photo stock sites?
I find it quite fulfilling to see my photos being used as the inspiration or the illustration for articles, banners, logos and other things and it always warms my heart

Nope, I used to have some on a paid stock site but the return on time invested wasn't worth the work involved.
No, I actually don't do much "stock" images because I always have a concept in the back of my mind when I start taking pictures. But I've discovered some time ago triggerimage.co.uk, where you can share your retouched images for licensing, book covers, etc. And it's a great way to make some money too

It'd be hard for me to. As EnglishBob says, it's just not worth basically selling your photos for the amount you get back.
I once thought about selling my photos in some stock photo site but they required a better camera model than the one I had. Besides, like people say, it's not that productive economically.