Through a combination of software advancement, and the continuing influence of remixes and hip-hop, the popularity of MP3s and generous dollops of humor and pop-sense both, a new bootleg scene exploded in the U.K. and elsewhere around the world in the early years of the 21st century. Rather than applying to rare or unreleased tracks per se, bootlegs here referred to any number of reworked songs that, in the most common and simply understood sense, fused the singing and lyrics from a song (or songs) with the backing music of another (or others). This three-disc MP3 collection, Boom Selection: Issue 01, brought together by the folks behind the Boom Selection website (which ended up as ground central for the whole phenomenon), acts as an extensive and often entertaining artifact for it all. It's not organized in any conventional sense beyond a few general groupings of key artists (most notably Freelance Hellraiser and Osymyso, both of whom contributed crucial songs in the trend's development -- respectively, the fantastic Strokes/Christina Aguilera fusion "A Stroke of Genius," and the outrageous "Intro-Introspection," a 12-minute collage of opening moments from decades' worth of pop hits). But if this isn't put together with the care of a Rhino box set, say, in terms of over the top near-endless pop thrills and new listening experiences, it is still an amazing collection. Since it spans three MP3 discs, there's almost two days worth of music available. While the compilers wisely expanded the collection to include pioneer work (particularly that of John Oswald and the Evolution Control Committee, whose Public Enemy/Herb Alpert combinations arguably defined the bootleg style as it came to be known), plus other songs that aren't bootlegs, per se, but either have a similar free spirit or just sound good. Thus the appearance of everyone from Gloria Jones and Andrew Loog Oldham to the Beta Band and MC Pitman, and more besides. Add in a slew of radio mix sessions that demonstrate the spirit of bootlegs gone even more berserk -- Osymyso and Freelance Hellraiser have turns, as well as the Avalanches, DJ Shadow, and Soulwax, -- and one ends up with music that at its best entertains, surprises, and challenges all at once.