TiddlyWiki: Adding warning and tip macros
I am a *very* big fan of TiddlyWiki5 (github). I use it to document just about anything I figure out while working on projects, setting up systems, … Anything I would otherwise quickly forget. It makes it easier to add structure to random tidbits of information, and forcing myself to document while I work on something helps to stay focused on a certain goal.
I noticed some of the official documentation Tiddlers had options to emphasize tips and (more importantly) warnings, such as these: