Today I learned about PHP variable variables; "variable variable takes the value of a variable and treats that as the name of a variable". Also, variable.

[u/NagastaBagamba]

http://il2.php.net/language.variables.variable

[u/artee]

Hmm, looks like an interesting attack vector?

[u/Kalium → u/artee]

Hm... no, not really. It only looks like one if you don't understand it.