Merb - Lightweight MVC Ruby app server. For high performance dynamic pages.
approval
Merb seems to be a lighter framework than Ruby on Rails, with more attention paid to concurrency and speed. Their file upload handler seems especially good compared to Rails. From the readme: \r\n\r\n\"File uploads\r\n\r\nThis is one of the things that Merb was written for. Rails doesn‘t allow multiple concurrent file uploads at once without blocking an entire rails backend for each file upload. Merb allows multiple file uploads at once. When a file is uploaded with Merb, it gets put in a Tempfile. So you just want to copy it to the right place on the filesystem.\"