TCP/IP & DNS

• What is my IP?
• Ifconfig.me
• Groan my IP
• SpeedTest
• PingTest
• Visual traceroute
• GeoIP City Lite Lookup
• GeoIP City Lookup
• Reverse IP domain check
• Spam database lookup
• Pingability
• W3Who
• Down for everyone or just me?
• utrace
• RIPE Database
• Just ping
• nmap online

Design

• Color Scheme Designer
• Border radius
• Hex 2 RGBA Color Calculator
• Lorem Pixum
• Gradient editor
• FlexieJS Playground
• Smush.it
• CSS3 Buttons
• jQuery UI icons
• What the font
• PutsMail email checker

Development

• jsFiddle
• JS Beautifier
• JSLint
• Snipplr
• Javascript Unpacker
• Get Fractal
• Event KeyCode Test

Misc

• CronWTF
• Shapecatcher Unicode character recognition
• timestamp to date
• Credit cards numbers
• QR-code generator