QR codes in the listening center

Ok. I have to admit that up until this year I have HATED the listening center. Years ago when I first started teaching there were books with accompanying cassette tapes! NIGHTMARE! The tapes had to be flipped over, changed out with each book, and they were always getting chewed up. I tried getting individual "walkmans" to go with each taped book but I still ran into the problem of having to teach which buttons did what and they still had to be rewound, flipped over etc.... I thought it would get better when CD's came out. I found myself using all of my scholastic points to replace my taped books with CD versions. I got parents to donate individual CD players. Now, I wouldn't have any chewed up tapes. Right? Right, but..... I still had the problem with the buttons and they ran through batteries like crazy! Ugggg. Enter the digital age. Ahhhhh.... now i have three ipod touches, 2 mini ipads, a kindle fire, and a galaxy tab in my room. I set about on a mission to turn each of my CD's into a digital file that could be accessed easily by the kids without my help. I did this by using audacity. We have the software on our school computer but you can download it for free. (http://audacity.sourceforge.net/) Once I had each CD in Mp3 format, I tinkered around with making playlists. This just didn't work because at the beginning of the year, my techno-babies couldn't read. They could work an ipad with ease but they couldn't read the titles of the books well enough to locate them in the playlist. That is when I decided to try QR codes. I quickly uploaded each of my mp3 files to my dropbox and then copied the hyperlink and pasted it into qr code generator. (These are easily found by doing a search for qr code generator). From there I just print the codes onto stickers and affix them to the back of the books. The techno-babies now just pick a book, scan the code, and sit down to read. No buttons, No flipping, No chewed up tapes, and they have rechargeable batteries! YEAH! Also, the bonus...If I don't have a CD for a certain book, I can use audacity to record myself reading the book and do the same thing. Next goal....buy a tape to mp3 converter so I can put all of those old tapes to good use. Any recommendations?