CodeRay - Benchmarks
See the power of regular expressions!
The benchmark task here is to highlight 100 KB of Ruby and C++ code into HTML.
Tests were made on my Celeron 2GHz/512MB Sony VAIO Laptop.

Ruby

% ruby -rubygems -Ilib bench\bench.rb ruby comp
                          user     system      total        real
CodeRay               1.042000   0.010000   1.052000 (  1.092000)
  91.58 KB/sec
Syntax                9.854000   0.110000   9.964000 (  9.984000)
  10.02 KB/sec
SilverCity            0.000000   0.000000   0.000000 (  6.209000)
  16.11 KB/sec
	

C++

% ruby -rubygems -Ilib bench\bench.rb cpp comp
                          user     system      total        real
CodeRay               0.431000   0.030000   0.461000 (  0.471000)
  212.31 KB/sec
Syntax                                            [not available]

SilverCity            0.000000   0.010000   0.010000 (  7.261000)
	13.77 KB/sec
	
Looks like CodeRay is about 5 times faster then the two other highlighters.