Board Games and other group social activities.

I think coffee tables should be usable as game tables. And games should be items that can be stored in your sims inventory.

$2 for a pack of cards, a budget game option.
$10 for a portable chess set.
$50 for simopoly (monopoly) or scribble (pictionary), or the core rule book for the pen and paper game 'There's a dragon in the dungeon!'