Nimiq Tools
Nimiq Tools is a open source, community driven set of online and offline tools that can help you with simple tasks. Every tool is designed to fulfill one specific task. For example, if you are a developer you can use the Address information tool to get a Nimiq address in different formats. Or, as a user you can use the Generate Address tool if you quickly need a new keypair.
Nimiq Tools can run completely client side so most of the tools can run without internet. Tools that require an internet connection are marked with a 
icon.
Since the whole website runs client side, you can download a copy of the website, put it on a flashdrive and store it on a computer that doens’t have internet. Then you still can access the offline tools. This includes creating offline transactions, signing messages and more! All you have to do is open the index.html that comes included with the downloaded copy of the website.
New ideas or suggestions are always welcome. Feel free to create a new PR or issue on Github. Issues and PRs on Github can be found here and here respectively.