I didn't see this until just now. Yes, I used clicker training to teach Tristan some fun stuff. I didn't have a dog when I first learned about it, so he was my test pilot! He's actually a blast to train - he shapes very quickly. Our training has rather stalled, since he no longer likes food enough to train with it.
I never had issues with him getting pushy, but he's a horse who has had very, very good manners instilled in him all along. Feed the treat away from your body, and since the click marks the behavior, they learn quickly that food isn't available until they hear it.
Here are some old pictures of some of his tricks. I just handed my camera off to someone, so they aren't great timing or very clear in all cases, but they may give you some ideas to play with.
Smile (his cue is "say cheese" and me pointing a finger up)
I taught that one by holding a treat a bit out of his reach so he had to stretch his lip out to get it. Marking any movement of his upper lip.
Bow (cue is Tada, and me bowing at him)
The first one I completely free-shaped, starting with him just dropping his head.
Shake (cue is "Gimme paw" and me holding out my right hand)
This one was my first bad idea! I originally wanted him to reach out with his foot more, rather than just raise it up. I showed my friend our progress on it, and she said "You know he's going to nail you in the knee, right?". I brushed it off, and low and behold, a few days later, he did. So I re-shaped it into just lifting his foot up.
Kisses (cue is me pointing to my cheek and saying Can I have a kiss?)
I started by getting him to lick my hand, moving my hand up to my face, then eventually removing my hand.
Stick out your tongue (cue is me sticking my tongue out at him)
Freeshaped, just watching for him to move his mouth and tongue.
Yawn (cue is me yawning loudly and covering my mouth)
Captured behavior.
Shake your head (cue is me touching my forehead and saying "fix your hair")
Free shaped/captured
Spanish walk modified
Not really a trick we trained for fun, but the start of his passage training, back before his health went downhill and he was a real riding horse.
Frisbee
Taught to keep me from dying when he was on long term stall rest/handwalking. Having a game to do while we were walking kept him from losing his cool. Once he was back to being allowed to do more, we worked more on the behavior. He'll go get the frisbee, bring it back to me, and I'd started training him to 'throw' it back to me when I lost focus. Note that I flinch even when my horse throws a soft toy at me. I'm such a wimp.
Have fun with it! I love training with Tristan. It's mostly been a way of interacting with him while he's dealt with various illnesses/injuries over the years and couldn't work undersaddle. Yawning and kisses were both taught when he was on IV meds for Lyme and I had to stand in the stall with him for 30 minutes or so every day giving it to him. Frisbee was when he had torn a suspensory. If I could get him more interested in food, I'd clean everything up a bit more, since my timing has improved since I worked with him. Let me know if you come up with any fun tricks!
Edited to add my favorite story about training him. It was after I'd started training 'bow', which, as I said, was the first I'd free-shaped. I think it was the second one I'd ever trained after "smile". I was working in the barn, and happened to glance at his stall. Over and over, he'd bow, then stand up and look around, baffled and clearly expecting a treat. He'd try again. And again. Looking more and more frustrated. He clearly hadn't worked out that the cookie only came if I was actually there to give it to him!