At Meta, there was a tool called "Thanks Bot" where you could publicly thank a coworker, and it would alert them, their manager, and your manager.
Given that this tool was more "heavy", people at Meta tended to use it for thanking fairly large efforts.
Alex had a great coworker back at Portal who would use it to thank people whenever they just spent 5-10 minutes helping him with something. This took people by surprise as they weren't expecting such a thanks for something relatively minor.
Thank people for small and medium sized good deeds, whether they helped you or just did some really good work. Thanks is cheap - You always come out hugely "on top" in interactions where you give thanks: Giving thanks takes a few minutes tops and receiving helping often requires 10+ minutes of the other person's time.
If someone really went out of their to way to do something great, reach out to their manager and thank them there as well. This really deepens your thanks, and it helps them receive proper credit, which could even be reflected in performance review.