Yeah, singed is one my mainstays. If you keep a ward up you should have no trouble getting to tops second tower during lane phase. Unless the enemy has a lot of cc you should get +3 movespeed boots right away. I usually do this and then pick up 2 rods of ages. Even if you lose your lane once you have 2 you will snowball lategame.
Pushing second tower takes some practice, you'll want to ward the jungle bush nearest it. If some one shows up, run back down your lane. If they try to come from behind you, down the lane, you can tell if there's anyone waiting in the jungle. If not run off into the jungle. If there is someone in the jungle and coming down the lane, than retreat through their tower towards their base or along thief base wall. Come back out mid or bot lane/bot jungle. As soon as they leave again, circle back around and push your lane again. When you are chased into a bush be ready to toss them as they face check and run back the way they were chasing you from.
I see singed as the best morale breaker. He makes the other team feel impotent. And can rout the enemy team just by charging at them. Remember when the enemy is trying to fall back, its free damage for your team, as most teams aren't organized enough, or on the same page to do an orderly retreat. If you can make the enemy team feel like youre toying with them, and have nothing to lose, they'll start thinking they are losing, and playing like they've already been beat.