Linux does have a similar system. Hold down <Ctrl><Shift> and enter "u" followed by the character code. The other difference is that the code has to be in hex, so "@" is "40".
Run gucharmap to browse the Unicodes for your favourite characters, like <Ctrl><Shift>U263A for ☺.
The only catch is that it doesn't always work: in Fedora 6, it's vanished from OpenOffice ☹.
|