AdVenture Capitalist remains strangely compelling, at least for a little while after they add updates. When you can quickly double your earnings, there is something to do, which is a strange thing to ask of an idle game.
After ProgressQuest was the trope-maker for idle games, later games have added variable degrees of interactivity. Upgrades and mini-games seem to be the most common, along with a bit of clicking, usually important at the very start but quickly overwhelmed by passive sources of advancement. Until recently, upgrades were the only interactivity in AdVenture Capitalist. Anti-Idle has a large idling component but also a variety of mini-games. Cookie Clicker is closer to AdVenture Capitalist but has rewards for watching and clicking the special cookies, along with some … unusualness in its late game. Candy Box and A Dark Room both have idle mechanics for advancement but significant game components.
I was originally surprised by offline advancement in AdVenture Capitalist, but that seems to be (becoming?) more common in idle games than I knew. Clicker Heroes and Idle Blacksmith both keep generating advancement while you’re away. Anti-Idle has an offline mode, but when last I played, you set it for a fixed duration like planting Farmville crops.
Lots of little wind-up toys. I cannot say that many of them have much gameplay value, but the steady accumulation of effortless illusory progress is almost hypnotic. Perhaps the strangest thing is seeing non-ironic idle games. ProgressQuest and Cow Clicker were commentary on types of games; new idle games mostly mean it.