2 more pics
And I found the following tumblr site, the URL already says what it's about ^^
It's not limited to pictures of women/girls though, so in case you prefer not seeing other males having their pants unzipped and exposing themselves(some pictures also show genitals, sometimes even in erect state), you might wanna use the second link which let's you choose (via thumbnails) which pictures you want to view in full resolution (as opposed to the main page which shows the pics in full res right away)
So, here are the two links:
show-your-jeans-unzipped.tumblr.com --> full resolution pictures
show-your-jeans-unzipped.tumblr.com/archive --> thumbnails
Enjoy
P.S. On a sidenote, I tried something today:
I had to trim the hedge in the front yard/garden (I live in a small village and outside the centre, so the streets are kinda narrow and there is no space between them and the gardens, so you're close to the street when working in the front yard/garden). I wore some old jeans with a kinda long zipper, so I figured I might try if it unzips by itself if the zipper pull is not in locked position(facing downwards) but instead facing upwards and thus enabling the zipper to slide down by itself. I had tried this before on a pair of newer jeans I wear daily and it didn't work, probably depends on the quality of the zipper or if it is already worn out or not.
Anyways, so I put on the clothes I wear when I work in the garden, zipped up the jeans normally(and completely) except for leaving the zipper pull in the unlocked position. I then got outside, got the hedge trimmer ready and started trimming.
After an hour, I was done and it was time to check out the result of my little zipper experiment ^^ So I took a look at the zipper and it had gone from completely zipped to completely unzipped in one hour, hehe

I guess that's due to bending down, getting up again, rising up, etc. when hedge trimming so there is quite a lot of movement of the hips, etc. thus exerting force on the zipper and making it go down. And the sweater I wore didn't cover the crotch area of my jeans for most of the time because I often had to rise up as high as possible to reach the top of the hedge, making my body stretch and letting the sweater ride up. Anyways, I was quite satisfied with the result - except for not many people passing by (and the few ones who did didn't look in my direction, even two teenage girls on bicycles who passed by near the end - so I was only a few steps away from the street - didn't look in my direction ^^) as I was doing the trimming during lunch time (I always eat lunch quite late like at 2 pm while most people do so around 12 am) so my unzipped fly probably went unnoticed but at least the "unzipping by itself" part works so I will do this again next time I work in the front yard/garden and hope that more people will be passing by
Cheers