Old people vs. birds and butterflies

I'm giving a one hour talk at the local library on Thursday to some old people about bird and butterfly gardening. I think I have it pretty well covered- although I haven't had time to even start it... but I was wondering if you had any favorite bird/butterfly plants to recommend or any other tricks?

My favorite "trick" is to throw grubs as I find them, into the lawn. Robins gather and have a quick lunch and then are quick to remember me next time I come outside... Now when I'm out diggin' I have 100 beady eyes staring at me.

Oh! I'm sure the old people will love that one!