Upload a QR code image and extract the data out of it.
Compress and optimize images for a smaller image size but still high quality.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Extract email addresses from any kind of text content.
Make sure your passwords are good enough.
Take an IP and try to look for the domain/host associated with it.
Get approximate IP details.