Just to keep you guys posted, we're working together with AJShort to get this feature in a stable state. Its currently on a "feature branch", you can follow its development here:
http://open.silverstripe.com/browser/modules/sapphire/branches/nestedurls
http://open.silverstripe.com/browser/modules/jsparty/branches/nestedurls
http://open.silverstripe.com/browser/modules/cms/branches/nestedurls

Currently there's not a lot to see, but hopefully that will change when AJShort works his magic on there

You can see there's been a nice lot of development done on this in the last month:

http://open.silverstripe.com/log/modules/sapphire/branches/nestedurls?rev=64221 shows some of work done over that time period.

You can try it out for yourself by downloading the code via subversion -

Or you can download the zip at http://open.silverstripe.com/changeset/latest/phpinstaller/branches/nestledurls?old_path=/&filename=/phpinstaller/branches/nestledurls&format=zip I believe.

I don't think the code is production ready just yet but some good work being done so far

I have a site as such, where there are perhaps 100 Things, so having the urls be /Bar-[0-100] is really undesirable. Thanks for the work on this feature.

Thing
- Bar
- Baz
- Eggs
Thing2
- Bar
- Baz
- Eggs

By the way, if I'm currently building a site as shown above, is there anything I should do now to make it easier in the future to have the site nest urls? If I build the site now with the current functionality, will I be able to take advantage of this feature when and if it's implemented?

Thanks.