You can play Splinterlands if you have the time, but that is very little.. Adding HBD to savings is already a bit extra... Maybe create Merch and sell it on Etsy? Also, if you have a good reach on Hive you could collab with projects where you would do some marketing/promo.

My Dad @minigunner from @coldbeetrootsoup are going to create a game soon and maybe they need help promoting it on Hive.