n=10000
  Benchmark.bm(10) do |test|
    test.report("Date.strptime: ") do
      n.times {Date.strptime("20071001","%Y%m%d")}
    end 
    test.report("Date.parse: ") do
      n.times {Date.parse("20071001")}
    end 
    test.report("Time.now: ") do
      n.times {Time.now}
    end 
    test.report("Date.new: ") do
      n.times {Date.new(2007, 10, 1)}
    end 
    test.report("DateTime.civil: ") do
      n.times {DateTime.civil(2007, 10, 1)}
    end 
    test.report("DateTime.parse: ") do
      n.times {DateTime.parse("20071001")}
    end 
    test.report("DateTime.strptime: ") do
      n.times {DateTime.strptime("20071001","%Y%m%d")}
    end 
    test.report("Time.local: ") do
      n.times {Time.local(2007, "oct", 1)}
    end 
    test.report("Time.parse: ") do
      n.times {Time.parse("20071001")}
    end 
    test.report("Time.quick_parse: ") do
      n.times {Time.quick_parse("20071001")}
    end 
  end

  class Time
    class << self
      # Usage:  Time.quick_parse("YYYYMMDD")
      def quick_parse(date_str)
        local(date_str[0..3], 
              RFC2822_MONTH_NAME[date_str[4..5].to_i - 1],
              date_str[6..7])
      end
    end
  end

                      user        system      total        real
  Date.strptime:      2.890000    0.040000    2.930000    (  2.982972)
  Date.parse:         3.630000    0.050000    3.680000    (  3.755735)
  Time.now:           0.010000    0.000000    0.010000    (  0.008608)
  Date.new:           0.590000    0.010000    0.600000    (  0.597446)
  DateTime.civil:     1.640000    0.010000    1.650000    (  1.675539)
  DateTime.parse:     4.970000    0.050000    5.020000    (  5.066107)
  DateTime.strptime:  4.250000    0.050000    4.300000    (  4.342663)
  Time.local:         0.120000    0.000000    0.120000    (  0.123242)
  Time.parse:         1.720000    0.010000    1.730000    (  1.750917)
  Time.quick_parse:   0.150000    0.000000    0.150000    (  0.157280)

  ruby -v 
  ruby 1.8.6 (2008-03-03 patchlevel 114) [universal-darwin9.0]