Glow in the dark phosphorescent products, invisible until it gets dark. Firefly jars, starry ceiling, are pretty obvious, how about ... your manicure ... around a light switch ... your house number (the pizza delivery guy could find your house!)
Designspiration — Design Inspiration
Rain Umbrella Protection and insurance royalty free vector icon set vector art illustration
Check out Umbrella icon created by Tim Pertuch
Hotel Pictograms - Full Version by Robert Karpati, via Behance
A set of 350 pixel perfect glyphs icons, perfect for apps, websites or just about anything you can think of. You may use this icon set for both personal and commercial use, which means this resource can be used in any project without worrying about licensing.
Here are some simple icon designs. I like how easy clean they are and each one has a specific opening to it that allows the icon to be a part of the background. I also like how they are all see through and tie in well the background also.