A very regularly occuring dream is that I'm in a train and realize that I don't have a ticket (never happened IRL), so I want to buy an e-ticket, but the ticketing app does not work. The text changes all the time, the buttons move around, weird errors, and then I realize 'yep I'm in a dream again'.

The nicer lucid dreams are those were you can fly or make spectacular light and colors, but I find that it's usually a difficult balance to avoid waking up.