|  | Mike Oldfield |  | Tubular Bells III (1998) |  |  | Progressive Pop, Progressive Rock, New Age | - | 0 | 
|  | Ayreon |  | Into The Electric Castle (1998) |  |  | Progressive Metal | - | 0 | 
|  | Symphony X |  | Behind the Mask (1998) [Compilation] |  |  | Progressive Metal | - | 0 | 
|  | Electric Light Orchestra |  | Live at Wembley '78 (1998) [Live] |  |  | Progressive Rock, Art Rock, Pop Rock | - | 0 | 
|  | Frank Zappa |  | Mystery Disc (1998) |  |  | Experimental Rock, Progressive Rock, Art Rock | - | 0 | 
|  | Shadow Gallery |  | Tyranny (1998) |  |  | Progressive Metal | 85 | 1 | 
|  | Electric Light Orchestra |  | Live at Winterland '76 (1998) [Live] |  |  | Progressive Rock, Symphonic Prog, Art Rock | - | 0 | 
|  | Ozric Tentacles |  | Spice Doubt (1998) [Live] |  |  | Space Rock, Progressive Rock, Jam Band | - | 0 | 
|  | King Crimson |  | Live at the Marquee (1998) [Live] |  |  | Progressive Rock, Jazz Fusion | - | 0 | 
|  | Fates Warning |  | Still Life (1998) [Live] |  |  | Progressive Metal | - | 0 | 
|  | Trans-Siberian Orchestra |  | The Christmas Attic (1998) |  |  | Christmas Music, Symphonic Rock, Progressive Rock, Symphonic Metal | - | 0 | 
|  | Kansas |  | King Biscuit Flower Hour Presents (1998) [Live] |  |  | Progressive Hard Rock | - | 0 | 
|  | Dream Theater |  | Once in a Live Time (1998) [Live] |  |  | Progressive Metal | 85 | 1 | 
|  | Avalon |  | Vision Eden (1998) |  |  | Power Metal, Progressive Metal | - | 0 | 
|  | Devin Townsend |  | Infinity (1998) |  |  | Progressive Metal, Industrial Metal | - | 0 | 
|  | Meshuggah |  | Chaosphere (1998) |  |  | Progressive Metal, Post-Thrash Metal | - | 0 | 
|  | Steve Vai |  | Flex-Able Leftovers (1998) [EP] |  |  | Hard Rock, Art Rock, Progressive Rock | - | 0 | 
|  | Threshold |  | Clone (1998) |  |  | Progressive Metal | - | 0 | 
|  | Rush |  | Different Stages Live (1998) [Live] |  |  | Progressive Rock, Hard Rock | - | 0 | 
|  | King Crimson |  | Live at Jacksonville (1998) [Live] |  |  | Progressive Rock, Jazz Fusion | - | 0 | 
|  | Symphony X |  | Prelude to the Millennium (1998) [Compilation] |  |  | Progressive Metal | - | 0 | 
|  | Porcupine Tree |  | Metanoia (1998) [Compilation] |  |  | Progressive Rock, Space Rock, Ambient, Psychedelic Rock | - | 0 | 
|  | A.C.T |  | Today's Report (1999) |  |  | Progressive Metal | - | 0 | 
|  | Artension |  | Forces Of Nature (1999) |  |  | Progressive Metal | - | 0 | 
|  | DGM |  | Wings Of Time (1999) |  |  | Progressive Metal | - | 0 | 
|  | Dreamscape |  | Very (1999) |  |  | Progressive Metal | - | 0 | 
|  | Jeremy |  | Live (1999) [Live] |  |  | Progressive Metal | - | 0 | 
|  | Jordan Rudess |  | Resonance (1999) |  |  | Progressive Rock, Progressive Metal | - | 0 | 
|  | Psychotic Waltz |  | Dark Millenium (1999) |  |  | Progressive Metal | - | 0 | 
|  | Derek Sherinian |  | Planet X (1999) |  |  | Progressive Metal, Progressive Rock | - | 0 |