Abilify is a new drug (atypical antipsychotic) that is a lot like rispiridone but less side effects, meant to be weight neutral... I just started a month ago and so far so good, was on rispiridone before that but had some weight gain (most people don't) and elevated prolactin (common side effect), also some sedation (I'm really sensitive to sedation side effects - most people ok I think). So far no probs with abilify.
Seroquel would do the same job but much more sedating. Also I think it is cheaper. Not sure about weight gain.

All of these drugs act as really good mood stabilisers - esp anti manic properties.