First off all I have to say that there are more than 20 available tools right now and more than 10 that will be available very soon. When you open the page the first few tools are about your, or any other, IP address. You can find the geographical location of it, find detailed information about the IP, ping your IP and the awesome tool IP range for that certain IP. Not only that eBrahma tools will offer you tools that will convert decimal IP into an IP and conversely, IP into decimal IP. On the other hand, if you are interested in IPv4 and IPv6 Subnet, there are calculators that will give you precise information. I tried all these tools for the IP I had problems and they gave me incredible help.
When it comes to domains, eBrahma also offers various tools that can give you valuable information. You can lookup DNS record from a domain (you can do that for an IP as well). The Domain Audit tool will show you the public record for certain domain and the web http header tool will show you what server features are active. What I also like very much is that there is domain availability tool that will show you if some desired URL is available. Also you can check is certain domain is black-listed.
I am also very impressed by the URL analyzer tool. It showed such broad and detailed information like meta data, text, links, images and processing time of my domain, which is kinda cool because you can do the same thing for your competitor if you doing SEO.
Additionally, the guys from eBrahma offer some email tools as well. You can perform email test, if you have problem sending email to a user for example. You can check POP status, authorization and banner. Also, there is IMAP banner tool and SMTP Greetings and SMTP Banner.
There are also more than 10 tools that are yet to be published. You have to admit that there is huge amount of tools available for free. You can visit this website and try the tools here.