I worked with classic red balls for years, but I got sick and tired of playing hide and seek with them when they rolled off the table. I also got sick of the clown nose comments. This is why I further developed sponge magic.
I have spent many years developing material (plenty of classic sleights and several different routines) but the handling I do most often is a quick "Miser Dream." I slip my hands into my back pockets, grab the jumbo earplug in the left hand and one of the small earplugs into my right. Then I quickly pretend to "find" several earplugs on other people's elbows, ears, etc- and each time I pretend to put in into my left hand, but of course just hold out the same one earplug in my right.
To finish, I produce the earplug from my own ear (or wherever) and jam "everything" that is in my left hand into a spectator's hand. I just tap the back of their hand with the one small earplug and just stand back and SAY NOTHING - the longer they wait, the more tension builds and when they open their hand - BOOM. Talk about feeling like a REAL magician!
This is also a great trick for serious hecklers. They make some dumb comment and I say something back. And then when they make another dumb comment (which they almost always do) I just say, "I don't think you're listening," and I pretend to spot something in their ear. Finally, I just say "Ohhhh, that explains it!" and pretend to pull the jumbo earplug out of their ear. Without saying a word I've been able to make the heckler the butt of a great magic sight gag, with all his friends busting a gut. It's clear sailing for the rest of the show!
There are other great magicians who have created effects with stuff OTHER than sponges. "Lazarus" is a wonderful bar effect where the classic "do as I" routine is performed with matches.
"Re:Cap" is a very fresh transposition between a borrowed coin and the CAP of a salt shaker standing at the end of a table. Magicians constantly floor folks with this stunning opener for years.
There are a lot of different things magicians can do with sponges. Look around for a sponge magic trick to work into your routine. You'll be pleasantly surprised by the reactions you get from your audience.