Desk
Hades was sure most of the mortals would disagree, along with several of the more influential half-bloods, but cleaning up paperwork that had stack up on his desk was the easiest job: it was dealing with the aftermath that was always more difficult.
They all conveniently caught fire when they threatened to bury him in his study, and if the ones that survived the fire mostly unscathed tripped into another fire, it really wasn't his fault that they were so clumsy.
It was only when Persephone came storming in about something she had wanted from her garden having not arrived, that Hades decided to take a visit to the mortal world for a week – visiting floral shops along the way, hoping to find something that would appease his furious wife.
Still better than being buried in his paperwork.