I'm always losing my keys so I was super-thrilled to find this idea at technabob over the weekend. I couldn't bring myself to drill through a lego piece (!) but after raiding my sons lego box I found the perfect bit to attach the key to (lego part number 3176).
DIY Lego Keyholder - HomeHacks
Lego Key Holder and Note Clip : 6 Steps (with Pictures) - Instructables
25+ Awesome DIY LEGO Life Hacks to Try Today - Dengarden
Lego Keyring Wall Mountable Small Key Hanger – MP3D
Lego-nyckelhållare – Lego key holder
Lego Key Holder - Instructables
8 Best Unique Key Holder Designs For Every Home - Tradeindia
Weekend DIY: Lego Keychain Project - A Spoonful of Sugar
Make this fun Lego car key hanger in four easy steps
Lego Star Wars Project Idea - DIY Key Organizer
How to Build a Lego Key Chain + Key Holder
How to use LEGO bricks around the home
LEGO Set 853913-1 Key Hanger (2019 Gear > Key Chain)
How to Repurpose Your Old LEGO Bricks into a Functional Hanging Key Holder « MacGyverisms :: WonderHowTo