The default swaybar (the thing that, with the default config, is just a black rectangle at the top indicating workspaces and showing the time).

For me it's at the bottom and using a script invoking conky as a source to display stuff. And that stuff is:

• Time left till some important timestamp (usually that cute boys bd :3)
• Audio status (muted/disabled or volume) (Because that bastard loves to randomly unmute without me knowing and blasting random shit in class)
• Playerctl status (which is disabled currently, as it took 5 seconds to run when using spotifyd)
• Bluetooth status (either blocked (by rfkill), not connected or the devices connected)
• Wifi status (either blocked (by rfkill), not connected or the IPv6 and then wifi strength, mame and the IPv4)
• Ethernet status (either down or the IPv4)
• Battery status (charging etc., percentage and time left)
• How much space in the FS is free
• loadavg and temperature of CPU
• Formerly i8k data, including fans status, but that's not a thing anymore on my new Laptop
• memory used and memory easy free
• the current time (%a %F %T)

Nearly everything is colored based on status (interfaces down -> red, up -> green, battery full -> green, load memory usage over 90% -> red etc.)