Rectangular Text Selection
Simple text editors usually only allow you to select contiguous lines of text with your mouse. Sometimes, however, it is handy to be able to select a rectangular area of text for more precise cutting/copying/pasting or performing search/replace on. You can select a rectangular area in Padre by holding down Shift+Alt whilst selecting text with your mouse or the arrow keys.
For example, imagine you have the following nicely formatted hash assignment in a Perl source file:
my %hash = ( key1 => 'value1', key2 => 'value2', key3 => 'value3', );
With a rectangular text selection you can select only the keys, only the values, etc..