Every other DAW I know of and use has a way to play/record MIDI notes by playing keys on your computer keyboard. I could've sworn you could in ACID, too, but I can't find anything in the Help or in any menu or any button for it. Help? I'm travelling and don't have a MIDI keyboard with me but want to try out ACID again as it's the first DAW I used as a kid.

If this doesn't exist for some reason, I'd suggest the ACID team look at how Bitwig implemented it. Maybe you don't have this feature because shortcuts are already assigned to the keys that would be used to play MIDI notes, but Bitwig easily got around this by having the use-your-computer-keyboard-to-play-MIDI on/off assigned to caps lock, so your keyboard plays MIDI and controls octave when caps lock is on and when it's off those keys work for their normal shortcuts again. Simple workaround.

This feature is important to me because I primarily use Renoise, which is a typing-based DAW. Clicking and dragging notes can be very inefficient and clicking around a visual keyboard to audition melodies makes it impossible to audition notes with any kind of rhythm.