Gottfried Gewessler

The best bet will be find an artist that you love and get their opinion on the matter. Folks here can help point you n the direction of a good one if you let them know your location. From the sounds of, the people suggesting more organic ideas are on the right lines - snakes, dragons etc. As the scar ages and settles it'll still work with the design. If you go with something that requires a more... can't think of the word... definite placement of line (?) then if the scar alters it might not work anymore.
If anyone else knows what I mean, feel free to chime in. My words have gone.

Are you a fan of the bio-mechanical style of art?
A great artist who specializes in that could really make your idea work, if you're into it . . .

Snake tattoos always work. For anything. Which is why I have three.

Given the shape of your scar, something long with pattern/texture would probably work well. A snake, dragon, octopus, etc..

In all seriousness, what about a rokurokubi? Their necks can stretch and bend all kind of crazy ways and could definitely work around a scar. And theyre cool.

My bad. I misread your question. Train on a railroad track? Monorail cat?

I too got this massive motherfuckin' scar on my outer right thigh. Sliced the fucker down o the gristle...good times. Internal & external stitches which left a half inch X 3 inch scar.
It fucked up all the nerves & to this day can't even touch it let alone have it slammed with a machine.
But who gives a fuck, I just suit around it, and as close to it I could get just worked some fading cloud work around it.
What Iwar said, if ya can't have it worked over like myself, surround it with kick arse tattoos. Hey, as they say...chicks dig scars :)
Welcome mate.

Hello and welcome to LST!
Pfff.... Your English is great, and you know it! ;)
First off I would advise you to poke around this site for a while. Check out the gallery section, watch a couple interviews, work your way through a chunk of the http://www.lastsparrowtattoo.com/forum/general-tattoo-discussion/15-latest-tattoo-lowdown.html thread and get inspired! I'm sure you'll eventually find something that strikes you.
When you stumble across a tattoo that you like, then look up the person who did it. Chances are you'll like more of that person's work as well. Finding the right tattooer is just as important, if not more so, than picking the right design. If you tell us where you live I'm sure the community here will be more than happy to suggest some great tattooers in your area.
In my humble opinion there's also no need to force a meaning/story/"reflection of one's personality"-type deal into a tattoo design. A lot of first timers may feel a little anxious because of the permanence aspect of getting tattooed, and they think that linking it with some personal meaning will help take some of that pressure of (at least that was the case for me back in the day. Lots of thought went into the design, none in the execution).
If the idea works, then great, but if not there's no shame in getting a tattoo simply because you like tattoos. I suspect that a zipper design or a lightsaber might get old real fast, but who knows? Maybe if the right person did it, I'd have to swallow those words. I have definitely seen a lot of cool Star Wars tattoos over the years. This awesome Seth Wood piece suddenly sprung to mind:

But anyways, I really hope you post it up once you get it done. If I were you I'd keep that scar, and just surround it with good tattoos. This is of course unless it holds some kind of negative association for you.
And remember, the internet is great and all, but nothing can ever replace or equate to a good old-fashioned consultation :)
Good luck!
Is this where I'm supposed to write "or just get a crawling panther...."?