Since we're all requesting features... I want the ability to send messages to the spam folder with a custom filter. I receive certain types of spam that always get through, despite flagging it multiple times. They're easily killed with the "create filter" feature, but I end up having to send them to the trash, which is less than ideal, because now my trash is full of spam.

So, in summary, please add "send to spam" to the custom filter actions.