Legal images
I use Google Images Search anytime I need pictures for a talk, website, presentation, or idea scrapbook. It’s not obvious, but you can filter the search results for those images that let you legally reuse them. Click the Tools button (to the right of Settings) beneath the Google search box, select “Usage Rights” and then choose your filter. (You can also filter by color, size, type, etc., in addition to license directly from Advance Image Search page.) The results will be a pile of select images that have Creative Commons or other fair use status. — KK