A few that stood out to me:

• There are over one trillion SQLite databases in active use — likely more than all other database engines combined.
• It’s maintained by 3 people who don’t allow outside contributions.
• It originated from software problems on a US Warship and, when government contracts were shut down due to a political fight, the engineer said “I guess I have time to write that database engine”.
• There are over 600 lines of test code for every line of code.
• All source code files come with a blessing, including this line: “May you share freely, never taking more than you give.”
• They take backwards compatibility seriously:
  • Current version of SQLite (3) goes back to June 2004 and can still read/write files from then.
  • If they ship a bug, they won’t fix it.