General web site tools:

AlertBot Website Monitoring - Website monitoring service that tests web site availability, performance, and alerts webmaster of downtime. Also provides ftp, pop3, smtp, ip, and dns server monitoring.

DailyChanges.com - Tracking of all the latest name server changes. Updated daily. (Link of the month January 2004)

DNSstuff.com - Tons of tools here. Just to list a few: Ping test, several DNS lookups, Traceroute, WHOIS, spam database lookup, DNS timing test, etc.

HowAmazing.com - Collection of valuable free resources and tools for developing incredible websites.

InternetTrafficReport.com - The Internet Traffic Report monitors the flow of data around the world. It then displays a value between zero and 100. Higher values indicate faster and more reliable connections. (Link of the month February 2004)

Add live chat for help/support to your site only for $8.99 - Providing live help & support for sales and support response, real time visitor monitoring, proactive chat invitation, hits counter, 1operator multiple chat, chat transfer.

Netcraft.com - Interesting web hosting statistics. Most reliable web sites, most popular web server software, uptime statistics, etc. Check out the uptimes for: HostLead.com (Link of the month October 2003)

Whois.sc - WHOIS search (Link of the month September 2003)

Whoisd.com - List of the 100 oldest currently registered domain names. (Link of the month November 2003)

Search engine related tools:

Marketleap.com	Link popularity tool and other 'checking' tool
Free Google Monitor	Simple but awesome tool. Check your rankings on Google.
Google Rank	Easily Find Your Website Ranking in Google.
phpHacks.com	Find out when the Google bot visits your web site. Using this free script you will automatically be notified by e-mail when Google crawls your web site.
Alexa.com	Check your web site's alexa rank. Read more about it here.
Google Pagerank	To see a webpage's PR ( Pagerank ) you need to download this toolbar.
SubmitPlus.com	SubmitPlus has several free web site test tools: load time test, meta tags test
DNSstuff.com	Tons of tools here. Just to list a few: Ping test, several DNS lookups, Traceroute, WHOIS, spam database lookup, DNS timing test, etc.
BruceClay.com	Several search engine tools. I suggest you go have a look.
Overture.com	Find the the most popular keywords. Note: Overture calculates results from Yahoo, Iwon, Lycos, Altavista etc.
7Search.com	Finding the the most popular keywords on 7Search.
Wordtracker.com	Find the the most popular keywords. Wordtracker tends to be much more accurate. Please note that the free version only displays results from AltaVista one of the smaller search engines around.