EvilZone

In my experience the best practice projects are games. Here are some simple examples:

- Tune sports cars and race them
- Manage a sports team and compete vs other teams
- Setup an army and fight vs another army

Stuff like that. It's just that games raise a lot of questions and usually require more creativity than copying functionality like making a simple bb script.
But if you want an idea like that instead, a good example is to try and copy librarything.com or to make a simplified version of deviantart.com

Ok, here's an update.

First of all - thanks, guys, you've been really helpful.

I've gone through a lot of tools and options and I finally came to a conclusion that there are pretty awesome tools that do that already. None of them seem to be 100% accurate, but it's to be expected given the nature of the task.
I'm not sure whether it's worth implementing another tool, especially since it will rely on others to work, and will not yield much better results than the rest. But if I were to, I'd have it do the following:
- Do a preliminary filtering out IPs which don't have HTTP and HTTPS ports open
- Use a number of tools (listed later) which will return a list of domains
- Check each of the domain's A records (because the tools may have old information)
A tool like that would mostly be useful for a large amount of IPs which one would not want to do manually. If we want to do just a handful of check one can just do it manually with the following tools:


https://www.robtex.com/en/advisory/dns/127/0/0/1/ - provides lots of information including up to a 100 domains associated with an ip, but doesn't work all of the time - I get a lot of bad gateway errors


http://viewdns.info/ - lots of useful tools, and a very simple but very accurate reverse DNS lookup, free api with up to 250 requests monthly, probably the most accurate tool out there, still not 100% up-to-date


http://reverseip.domaintools.com/search/?q=127.0.0.1 - another very accurate reverse DNS tool, which provides up to 3 results for free - very useful for another layer of preliminary filtering. If it doesn't return anything, there probably isn't anything.


Here are a couple of IP neighbourhood checkers, which are really useful:


http://www.ipneighbour.com/ - returns accurate results
https://majestic.com/reports/neighbourhood-checker - returns nice results for reverse DNS look up as part of neighbors, allows only so many checks before asks for registration


And a list of tools which don't do anything much different than what a simple gethostbyaddr() would return:

http://mxtoolbox.com/
http://remote.12dt.com/
https://www.dnswatch.info/
http://ping.eu/rev-lookup/
http://www.dnsgoodies.com/


If I decide to actually develop the class (it will probably be PHP or JAVA) I'll share it, but at the moment I don't think it's worth the time invested. Still had fun doing the research though.

The python snippet appears to provide the same information as php's gethostbyaddr. It shows some data, but it doesn't get all the domains which have A records pointed at the IP, which is what I'm looking for.