Hypemachine, an aggregator of the latest free songs posted on music blogs, has been around for years but I started using it with gusto this week and it’s tight. It scans all those blogs and then streams them for you in a popup radio player, which you can narrow by popular, new, or from the top 25 music blogs. If you like a track you can click through to the source blog and download the mp3. (Most of the time the mp3s have been released onto the internet by the artists themselves. If there’s ever a question, most have an option to buy the song on Amazon or iTunes). A great way to freshen up your music mix without having to think too hard or shell out. [Hypemachine]