Php, dynamic variable naming
I just found this out mostly by trial and error, and seem quite chuffed about it.
I have been moaning about PHP lack of deeper functions (Reflection, proper interfaces, generics). I am a C# guy by day and a PHP (CI) guy by night, and the difference in functionality really does get to me at times.
But here is my little code segment - You can have "dynamic " naming of functions like so:
$cat = "meow";
$noise = "cat";
echo $$noise;
//this will give you meow...
Simple stuff I guess, but it just made my life a little bit easier.