While writing your new post to your blog, you need to highlight a piece of source code. Now, what? Here is a list of 10 online services which could save you.
ToHtml.com by Oleg Parashchenko
The most "usable" online code highlighter service, supports a LOT of different languages including SQL, scripts, ancient language (*asm) and newest (.NET)

Quick HighLighter by Veign
A very easy to use website, supports a lot of languages, including PHP, ASP, VB.NET, C#, Ruby and "robots.txt" <--LOL

CodeColor by Asp.NET Resources
It has not many languages to work with and I don't like the idea to have a popoup window with the final highlighted code. It works pretty good though.

GeSHi by Nigel McNie
As written there... "Support for a wide range of popular languages, Easy to add a new language for highlighting, Highly customisable output formats". Excellent idea the option to setup your own highlighiting rules. A must have if you are the owner of a phpbb forum or a Mambo website.

ColorCode by Thomas Johansen hosted @ CsharpFriends by Salman Ahmed
Another very easy interface, altough with no options at all. It just supports C#, VB.NET, J# and T-SQL.

Pygments by Pocoo
Sntax highlighting engine written in Python. It supports many different languages. You can store your pieces of highlighted code for later use. Nice and clean interface. Does not support Visual Basic (which is like incredible)

Code Colorizer by Chami.com
"It can convert your ASP, C/C++, Clipper, Delphi/Pascal, HTML, Java, JavaScript and Visual Basic source code to colorized (syntax highlighted) HTML documents". Very simple interface with few languages supported.

Code Format by manoli.net
Another simple interface. It supports just C#, vb, aspx, html, xml, t.-sql and msh. The output conforms to the HTML 4.01 specification

ActiPro CodeHighlighter by ActiPro Software
This is the one I like more, not because it has something better than the others, but just because, in my eyes, is the easyer one use.

Syntax Highlighter for Microsoft Live Writer by xKnown
This is very very very cool! It's a plugin for Windows Live Writer which allow us to write highlighted source code directly within Windows Live Writer! The plugin can be downloaded @codeplex and Windows Live Writer can be downloaded here.
What's so cool about that? WLW allows you to post new articles directly to your blog (even Subtext!) and there is no need to use your blog platform interface. The plugin allows you to quickly insert an highlighted piece of code of your choice.
