Monetizing a database of tlds

During the last two years I've created some domain tools, some of them for our whois service, some for a greek list of domains, and in the progress I've made a crawler that gathered around 2,500,000 domains.

My question is, do you think there is a way to monetize this list? I don't really know what someone would do with it, so I can't figure who would need such a list.

If you think this can be sold, what would be a fair price? Thanks in advance for any response :)

hehe, I replaced my whois search with some domain check form from 1&1 my affiliate partner and have this way my earnings