Creative Market sells loads of design resources. From high quality stock photography and vector art, to print design and web templates, to really fancy stuff like Photoshop actions for getting awesome effects easily.
Once in a while, they put together a bundle of resources you can buy and then have access to download forever from your account. They are packed with all the great stuff I mentioned. Purchased individually, everything together would be quite expensive. But for this week only, the entire Big Bundle is priced at $39!
I love having stuff like this around. Often just poking through looking at everything I have is the creative spark I need to get started building something.