Here's a fun trick to do on the chinese hotel, watch everyone leave the room as you enter it
Works in public rooms too
1. Go to update your ID, and for your mission put "Hi!i:2", leave the update ID window open.
2. Go into artmoney and search and replace "Hi!i:2" with "Hi(ASCII 13)i:2"
3. Go back to habbo once you have changed the value, and press the done button on the update ID window.
4. Make a packet filter to replace "Hi(ASCII 13)i:2" with "Helllo", this will ensure you only error the room and not yourself.
5. Turn the filter on and see how everyone exits
This method can be used to do fake badges too, except without the packet filter part.
I TAKE NO CREDIT FOR THIS!! BUT I WAS ABLE TO POST IT HERE 
FOR YOU LITTLE 1337 SCRIPTERS AND HACKER, ROFL.