A couple that I like to hit are the arm spin and a cool fireman's carry off of a Russian tie (or a two-on-one for some of you out there) - but you don't actually even need to catch the leg, you just throw him over to his back with only the arm, which in my opinion puts a lot more pressure on him and makes it easier for him to go over.
Basic arm spin technique, though I don't normally hit it from that position. I like to hit the move when the guy has a collar tie or is kinda posting a bit near my shoulder, and I put my left arm right in the crook of his elbow (like, the position you would be in if you tried to hit a slide-by), then step in, bring my right arm shoulder deep, and execute the move. Plus, if you miss the arm, you're in a position where your level is changed and he's probably somewhat off-balance, so you can just shoot straight in on a double - a move I like to call the cinnamon twist.
The only setup I've ever used for the arm-only fireman's is off the Russian, though I'm sure you could find another way if you experimented around. I do this when he tries to grab my near-wrist that I have on his bicep. Basically, I just circle that leg in and when he steps, I duck my head under his arm, step in, and go to my knees, basically like what you'd do with a normal fireman's carry but only not bothering to catch the leg. Make sure that you keep both of your hands tight to your own chest, effectively keeping his arm very tight to you and enhancing the pressure. Then, you can just basically take him over your shoulders and put him straight on his back.
I don't know if you would count footsweeps and inside trips as throws, but something that I've always liked to hit in an over-under situation is a combination of the two. First, circle him towards the side you have the overhook on, and as he's stepping, attempt to hit an inside trip on that leg. If you get the inside trip, great, take him over, but if he steps that leg back, then you have a nice footsweep open. What you basically do is, right as he steps that leg back, use your overhook arm and give him a nice push on that side to take him off balance and hopefully off of his feet. Use some force with the push - if you're too light, it won't take him off his feet and it won't move him. Right as you're pushing him, stick your foot out to the side that he's being pushed towards, and if you pushed him right, he'll be taken off of his feet and straight to his back because basically, you tripped him, or swept him off his feet (hence the name footsweep).
This move takes a lot of practice and sorry if my description was somewhat confusing - it's a complicated move, but it's been very good to me and at least it's a change from the lateral drop that everyone expects in an over-under. My coach taught it to me about two years ago and I still only hit it successfully in a match around nine months back, but it's always worked for me once I finally learned it.
Anyways, those are the three big moves that I like hitting that not many people see coming. Good if you need points - but remember, you can't make a living off of throws. Single legs, double legs, high crotches, short offense, etc. are all things you need to work on as well to be successful at neutral.