Web Sites That Do Exactly What They Say They Do

Kids these days have the most convoluted web site names. Facebook? Twitter? eBay? I'm sorry, but I like my coffee black and my web sites self-explanatory. Here's a handful of actually useful web sites that do exactly what they sound like.
Speedtest.net: If you're curious how fast your internet is for any reason, this is the site to check. It'll give you both and upload and download speed, so you can find out if you're getting what you pay for (or if you're just getting faster speeds than your friends). Just load it up and click "Begin Test" to get started.
Down For Everyone or Just Me : If you're getting an error when visiting a certain site, it could be down—or something could be wrong on your end. To see which it is, head to Downforeveryoneorjustme.com and type in the web site's domain. It'll let you know if it's actually down or whether you need to do a little more troubleshooting. You can head there quicker by typing in isup.me.
How Secure Is My Password?: Does what it says on the tin. Type in a password and it'll tell you how long it would take to crack.
What's My IP: Whether you're setting up a home media server with Subsonic or you just need to SSH into a computer at home, sometimes you need to know a computer's IP address from outside of your network, and this site will tell you what it is. Just visit it from the computer in question and it'll give you your IP address. Whatsmyip.org is the simplest iteration of this tool, though Whatismyip.com contains some handy information about IP addresses if you're new to networking, and IPChicken.com gives you a bit more than just your IP, like your remote port and browser info. Not to mention a funny picture of a chicken.
Can You See Me: If you're having connection issues with a certain program, like email, IM, or BitTorrent, it could be because your firewall or ISP is blocking a certain port that program needs. Canyouseeme.org will let you type in a port and check if it's open— if it isn't, then that could be the source of your trouble. If it's open, then you know it's something else.
Who.Is: This site uses the Whois command to find the IP address, location, server type, and other statas of a specific domain. It's useful for finding out more about your favorite sites, testing your own home webserver, or trying to ping an outside IP address when you're having DNS troubles.
Where's My Cellphone?: We've all lost our cellphones in the couch cushions at one time or another, and when you just can't seem to find it, Where's My Cellphone can help you out. Type in your number and it'll ring your phone for you so you can search it out. It's really useful if you don't have another phone in the house to call your phone with.
Is It Old?: Have you ever discovered a site, page, or hilarious YouTube video that all your friends just needed to see? Have you ever had them all respond with "dude, this is from 10 months ago". Is It Old tells you how long a page is and how many times it's already been tweeted, so you know whether you're sharing old news or not. Just paste in the URL and hit the button—it'll let you know whether it's worth sharing.
Free My PDF: Free My PDF will get rid of PDFs that have restrictions on printing, copying text, or password-protected editing. It won't crack a PDF's password—that is, if it requires a password to be viewed, this won't work—but if you have any other types of protected PDFs, just upload them to Free My PDF and it'll spit out a liberated version for you to do with as you please.