favourite Gentle Giant riff (guitar or moog)

OK.

thellama73 wrote: I too love the In A Glass House riff (in 13/8 I think)

Actually, it's more complicated than that. The riff is divided into three segments: The first ("Shadow fills the light") is in 7/8, the second ("until the glass house becomes the night") is in 5/4 and the third ("the dark is gleaming or am I dreaming") is in 6/4. Together, that yields 29/8. I love John Weathers' drum accompaniment. The guy (actually, the whole band) has an incredible talent for making complexity sound so easy.

And because they wrote so many awesome riffs, I feel obliged to list a few more besides "Prologue" (which I already mentioned):

• The verse riff of "Giant" (and the subtly grooving bass riff in the middle section)
  
• The main riffs of "Why Not?" and "Plain Truth", two awesome blues rock songs that prove that GG were good at anything
• The riff that concludes each verse of "Pantagruel's Nativity" is orgasmic (the mellotron support helps a lot!). And yes, the riff in the middle section. Great contrast between the two
• The riff at the very beginning of "The Runaway" convinced me that this band is awesome

I find that as their career progressed and their writing got really multilayered, they relied less on single riffs and more on the interaction of several melody lines. Which is also awesome, just in a different way.

nice guitar riffs here also

HarbouringTheSoul wrote: The riff that concludes each verse of "Pantagruel's Nativity" is orgasmic (the mellotron support helps a lot!). And yes, the riff in the middle section. Great contrast between the two

I found the riff on 'So Sincere' pretty tight.

Epignosis wrote: The main theme of "Playing the Game" is awesome.