http://growthtext.com/free-stock-photos/
I'm a sucker for beautiful presentations. Blame it on being in that company for 4 years.
One of the thing that we use most is stock images and here's a blogpost from someone who'd exhaustively gathered the best and free:
http://www.everystockphoto.com (searches from a few sites, some may not be free)
http://www.brandsoftheworld.com/ - Collection of brands & logos from the world
EDIT: 2015 May
I've found new love for making quotes tailored for social media and that requires a different type of stock photos.
Here's the new list for quote creation stock photos:
https://www.lum3n.com/
http://www.entrepreneur.com/article/238646
https://designschool.canva.com/blog/free-stock-photos/
I need to check this out too:
http://benrequena.com/find-free-stock-images/
LOVE
Not searchable
https://unsplash.com/ - Creative Commons Zero. Oh my! Quantity and quality! Score!
http://picography.co/ - Creative Commons Zero
http://getrefe.com/ - Creative Commons Zero, might be searchable soon.
http://jaymantri.com/ - Creative Commons Zero
http://publicdomainarchive.com/ - Creative Commons Zero, Gorgeous!!! Professional!
http://www.gratisography.com/ - Woah!!! Absolutely gorgeous artistic creations. One of a kind. Very specific! Creative Commons Zero
http://travelcoffeebook.com/archive - Gorgeous one of a kind. Creative Commons Zero.
http://skitterphoto.com/ - Toooooo gorgeous! One of a kind. Creative Commons Zero.
http://littlevisuals.co/ - Beautiful small library. One of a kind. Creative Commons Zero.
http://www.lifeofpix.com/- Quite beautiful
http://epicantus.tumblr.com/ - Not bad :)
http://www.designerspics.com/ - Mostly specific stock photos with thematic use.
Attribution
http://superfamous.com/ - Creative Commons 3.0 (credit)
http://raumrot.com/ - OMG OMG! Too gorgeous. Attribution required. But so gorgeous! Small library :)
http://foodiesfeed.com/ - Only on food. GORGEOUS!
With categories
http://www.upicm.com/ - Not bad :)
http://stokpic.com/ - Not bad. Require attribution.
SEARCHABLE
https://picjumbo.com/ - Searchable! Yes! Gorgeous!
http://pixabay.com/ - Also searchable. Also gorgeous!
http://isorepublic.com/ - Woah so gorgeous. One of a kind.
http://www.rgbstock.com/ - Check for attribution. Gorgeous :)
http://www.pexels.com/ - Very gorgeous!!! Require attribution.
http://magdeleine.co/browse/- Tooooo beautiful. Attribution required.
http://kaboompics.com/ - Gorgeous! Attribution.
http://finda.photo/ - META SEARCH for the unsearchable sites above. Search by colours.
PATTERNS
http://thepatternlibrary.com/ - with attribution.
TEXTURES
http://www.cgtextures.com/
VECTOR GRAPHICS
http://www.freepik.com/
INSPIRATIONAL
https://niice.co/
COLOUR PALETTE
http://www.pictaculous.com/
http://www.colourlovers.com/
An article by canva: https://designschool.canva.com/blog/color-tips/
