Check out these funsters who claim to be Googlebot and can't seem to follow robots.txt: A bad robot hit /bot-trap/index.php 2007-12-11 (Tue) 04:14:10 address is 89.149.244.117, hostname is 89-149-244-117.internetserviceteam.com, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /bot-trap/index.php 2007-12-03 (Mon) 18:57:56 address is 66.109.20.28, hostname is 66.109.20.28, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /lang/ko/bot-trap/index.php 2007-11-19 (Mon) 05:47:36 address is 74.62.153.11, hostname is rrcs-74-62-153-11.west.biz.rr.com, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /bot-trap/index.php 2007-11-18 (Sun) 17:34:06 address is 64.141.108.29, hostname is 64.141.108.29, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /bot-trap/index.php 2007-11-12 (Mon) 15:32:25 address is 62.31.213.213, hostname is 62-31-213-213.cable.ubr12.azte.blueyonder.co.uk, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /bot-trap/index.php 2007-11-09 (Fri) 00:53:58 address is 72.232.196.154, hostname is 154.196.232.72.static.reverse.ltdomains.com, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /bot-trap/index.php 2007-10-29 (Mon) 03:59:44 address is 208.53.183.104, hostname is kaskus.mobi, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /bot-trap/index.php 2007-10-20 (Sat) 20:11:18 address is 71.162.124.154, hostname is static-71-162-124-154.bstnma.fios.verizon.net, agent is Google Spider A bad robot hit /bot-trap/index.php 2007-10-19 (Fri) 17:18:25 address is 71.162.124.164, hostname is static-71-162-124-164.bstnma.fios.verizon.net, agent is Google Spider A bad robot hit /bot-trap/index.php 2007-09-29 (Sat) 09:59:22 address is 213.171.218.82, hostname is server213-171-218-82.livedns.org.uk, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) A bad robot hit /bot-trap/index.php 2007-09-17 (Mon) 22:15:45 address is 60.191.5.154, hostname is 60.191.5.154, agent is Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html) (via babelfish.yahoo.com) bot-trap automatically blocked all of these bad actors.
bot-trap looks good the only thing that concerns me about it is that some of the blocked bots could be from search engines but pose as googlebot and are too primitive to follow robots.txt thus preventing your site from being indexed in new search engines.
If they are legit, I can't imagine them posing as Googlebot. If they can't follow robots.txt, I don't want 'em on my sites. Most bots just eat bandwidth and return nothing.