Well, anything not related to lighting. Yamaha MusicCast, Roon, Google Nest/Home, Android (with Google TV) Streaming Boxes, UniFi Protect, HP Printer, LG TV, Yamaha Receiver, Energy monitor, Water monitor, Solar Panels.
HomeMatic has been integrated in IPS, it would be great if IPS could be integrated in HA. I don’t think there is a module or integration available for that, but I assume it should be doable with MQTT.