Galeo is state-of-the-art geolocation calculator. You can use it to locate remote IP address using classic ping or traceroute utilities.
The system measures the quality of connections between all acting networks. It guesses and measures various parameters. This way it gets a lot of data to guess the network topology and calculate the positions of any network element. The technique is similar to weather forecast, so that the computation is time consuming and requires you to employ multi-core computers.
The following example shows the performance of the algorithm using 9.6km (6miles) calibration precision. The target is seznam.cz site - one of the largest search services in the Czech republic. The next four pictures represent four snapshots of the network where the algorithm detected the target site.
Finally, the four snapshots (and many supporting measurements) imply the final result: the location is Prague (50°3'37.325"N, 14°25'10.929"E), diameter 45km.
Yes, the target is located in Prague.
According to various public tests, the SPOTTER algorithm is supposed to be one of the best... let us use its public service for the same task - the location of seznam.cz site. The result is less accurate: 183km (114miles) away, and the diameter is more than 3600km (2250miles)! Here is the respective visualization:
Output of the SPOTTER algorithm.