I am decidedly not a defender of mainstream music magazines, but in the mid-80s to early-90s, Spin was the only game in town if you were a kid living in a part of the country with little access to pop culture beyond top forty radio or basic cable. I'm pretty sure Spin is where I first heard of bands like the Replacements or the Pixies long before radio took a chance. (True story: the local "rawk!" station actually played the Replacements a little later on in their careet, usually sandwiched between The Allman Brothers and probably Warrant.)
So while normally I would suggest throwing your magazine dollars toward independently published ones (assuming you can find any theses days), Spin's 25th Anniversary Issue is a fun trip down memory lane. Sadly, but expectedly, women were reduced to a mere footnote with short features on Liz Phair's Exile In Guyville ("Fiona Apple, Katy Perry, and even Lady Gaga were likely listening, but so were a lot of guys."), plus Sleater-Kinney, Fiona Apple, Missy Elliott, and Lily Allen's rise to fame via MySpace.
For an even bigger trip down memory lane, all the back issues of Spin are available at Google Books .