sup3rS3cretMes5age - A safe, simple tool for one-time (self-destructing) messages
Micro Snitch - Micro Snitch is an ultra-light menu bar application that operates inconspicuously. It helps figuring out if someone’s spying on you.
Mailinator - Any Inbox. Any Time.
Oversight - Get notified when an app accesses your Mac's camera or mic
10 Minute Mail - Temporary disposable e-mail service to beat spam. Avoid spam with a free secure e-mail address.
Little Snitch - Little Snitch is a firewall application that monitors and controls outbound internet traffic.