I just created a Google Code SVN repository for storing my school projects and homework, and to allow easy transferring between school and home.
Its default directories i
One of main goals that tracks with folder lay-outing (in versioning), is Access Control Management.
If there is need for separating Develop team ( who works on Trunk) and Maintain team (who dealing with Branches) this structure is good:
/trunk
/Project1
/Project2
/branches
/Project1
/Project2
/tags
/Project1
/Project2
And if we want to permit access of every project to a specific user group , this structure is good:
/Project1
/trunk
/branches
/tags
/Project2
/trunk
/branches
/tags