SYL's sound can't be described by words, their material from album to album and song to song really varies so much, in a way.
Some say they are the most extreme band there is... to me it is controlled chaos, a huge wall of sound that can melt faces...arg i love it. There is also an element of humour in the music, which is hard to understand unless you hear it for yourself.
Some of their music is industrial influenced, but it's not electronic music at all. The first album used a drum machine and it was Devin Townsend's first album since he sang on VAI's sex and religion. It blew people away. Then he got Hoglan on drums and the rest of SYL together and wrote and produced the album "CITY", which is highly regarded as one of the best metal releases ever, even though the band is still reletively unknown, they have one of the most serious underground following. ( esp in Canada)
A number of year's later they released the album SYL, which was solid but not their best. Then in 05 they released "ALIEN", which is the most extreme album i've ever heard. It's incredible. They just released a Fifth and final album called "The New Black", which is very good, a bit more technical musically and also more accessable.
Watch the vid of the new song "Wrong Side" by Strapping Young Lad, it will give you a general idea of the band.
http://youtube.com/watch?v=T6AtBoTlQd4&search=strapping%20young%20lad
This said, devin townsend has also released 6 amazing solo albums, and produced a number other band's records, such as Soilwork's "Natural Born Chaos".