National Record Store Day. Not only will you find music-lovers and other similar nerdery in those shops, but many artists provide special one-day only vinyl only releases. Here's a list of special releases for the day.
I also stumbled on this great website for those who might be curious about where the original samples for some of their favorite hip hop tracks came from. Hip Hop Is Read has been building a Sample Set Index for some time now, and it's a fascinating resources to explore -- be ready to set aside time to listen, though.
Record Store Day 2014
Hip Hop Is Read - Sample Set Index