Powershell to give my a sites template

Can anyone help with this.

I have a sharepoint 2010 farm. However, we have some fab 40 sites active on the site. I would like to find out which sites are using the fab 40 templates.

Does anyone know of a PowerShell script that wil go through all of my sites and report back the template being used. I'd like to output it to a csv file with the path to the sites and the template.

Thanks for any help 

LSTalbot