Sometimes making music or beats isn't the only thing you can do with LMMS. I find it also useful and flexible in producing various sound effects. I can't say my examples are the best, but there may be a bit that can be learned from them.

Making a helicopter sound:
http://www.youtube.com/watch?v=v_xT1gvhtD4

Making a siren (air raid/tornado) sound:
http://www.youtube.com/watch?v=PIQFyliz_bU