I've really enjoyed reading some of the stories posted here, so I thought I'd contribute my own.
I live at home in the summers. Our family also has a very secluded cottage in the northern part of our state, and we go there often. However, since I was working, I couldn't get there as often. This also meant that I had a good excuse to go even when nobody else did, so I'd get the cottage all to myself.
Well, this was a great opportunity to spend a weekend naked in the sun. And of course, that led to masturbation. I love to use a butt plug - I love the feeling of fullness it creates. But on one trip I decided to go a little further, so I pulled into a sex shop along the way and bought big dildo. Heh, I was hard for practically the whole 3-hour drive up to the cottage, just thinking about what I'd do to myself that weekend. When I got to the dark stretches of highway near the cottage, I took off my clothes and drove naked - of course, it was night by then, so no one could see me, but it was thrilling anyway.
When I got there, I put in the butt plug for a while to loosen myself up, but found I couldn't wait, and ripped open the dildo, lubed it up, and began pushing it in. Wow! It was really stretching me out, but it felt sooo good that I just had to masturbate right there.
The next day I took my new toy outside. Mmm... I love the feeling of rolling around in the grass naked, and ramming myself with a think 8' dildo made it even better. I tried some clothespins on my scrotum. It hurt a bit, but started to feel really good, too. After I finished with myself, I went down to the lake to have a skinny dip and then lay on the dock for a while. I had to cover myself a little, because there were boats passing nearby, but I left as much uncovered as I could.
Sunday was the same - lots of pleasuring myself and my anus. I went up north by myself many times after that!