Its worth nothing.
If you can call companies and can sell it, then bingo, you not only sell a domain, but you have found yourself a new career selling on the phone, because, if you can sell that your a genius lol
The only way you have a chance is to build a site, get repeat custom by giving great tips and capturing as many revenue streams from your visitors as possible.
Unfortunately, unless your pretty good at all the above, the time and effort taken will never equal the amount you may make.
The only reason no one is replying with a valuation is, they have all said this a million times to people.
Remember it fondly and let it go.