When adding custom entities to Microsoft Dynamics CRM, adding icons for you entities is an important fit and finish detail. However, finding the right icon in the right size can sometimes be a challenge.
Here are two of my favorite resources for finding flat icons that generally look good in CRM 2015.
www.flaticons.net Includes 2,500 free flat icons available in the size and color of your choice, as well as an icon maker.
https://icons8.com 15,400 free flat icons in any format, size, and color
Between these two sites, you can find just about any icon you want. Got any others to recommend? Post them in the comments.