PostHaste, a free app for Mac and PC from Digital Rebellion, can help you stay organised and save time on every single project you work on.
It does this through instantly creating a bespoke folder structure and project files based on any number of different user defined templates.
It can also automatically add in specific variables such as the date, project name, client name etc. into the template structure too.
There are two 'halves' to PostHaste, the template creation side and the Project creation side, which makes the folder structures as specified by the template + any variables you input.
Post Haste gives you a huge amount of flexibility in how you create your templates, including 16 different ways to layout the date (see p.10/11 of the manual), incremental folder numbering and many other options.