I like CAML Query Builder. I use it often. Highly recommended. By specifying a URL and selecting a list, you can quickly build out your CAML query. There are a few things you need to be aware of however:
1. By default, the CAML query contains <Query>. If you include <Query>, the query will return all items in the list. To apply the query, remove <Query> and </Query>
<Query><OrderBy><FieldRef Name=’Sequence’/></OrderBy></Query>
2. The copy to clipboard includes double quotes which results in the error: CS1002: ; expected:
<OrderBy><FieldRef Name="Sequence"/></OrderBy>
To fix, just replace the double quotes with single quotes
<Query><OrderBy><FieldRef Name='Sequence'/></OrderBy></Query>
I’m sure these items are documented - I just missed them.
Update 1 (2/8/2008): Looks like Àlex Peláez ran into the same issue.