Please let me know if there is English errors on this page.

Tools

You can watch Nicovideo without an account
You can watch Nicovideo without an account.
You can watch Nicovideo without an account using the UserScript
It is more useful.
n-sided dice
It prints a random number from 1 to n.
YouTube and Amazon url shortener
It is a bookmarklet.
You can watch inappropriate videos on YouTube without an account
It is a bookmarklet.
Hex Base64 Converter
Convert Hex <-> Base64