IconsExtract - Extract icons and cursors stored in EXE, DLL, OCX, CPL files
draw.io - Online diagramming application
Quick Any2Ico - Quick Any2Ico is a FREE Portable Application that creates high quality Icon files from any File...
LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
IcoFX - IcoFX is an all-in-one solution for icon creation, extraction and editing.
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.