When installed, this add-in adds an entry to the right-click menu in VB code window. You can then select or right-click on opening parenthesis or quotation mark or VB keyword, such as IF, DO, FOR etc. Then select VBmatch from right-click menu. VBmatch will find matching syntax element: closing parenthesis, quotation mark, END IF, LOOP, NEXT etc. Additionally, VBmatch will select found range. VBmatch can handle nesting, comments and text strings. When matching doublequote VBmatch also calculates string length.
Update: version 2.0 can do backward matching.
Update: version 2.09 supports both VB5 and VB6, and can be launched via Edit toolbar (with icon 😉 and AddIns menu.