For example, here on stack overflow the URL https://stackoverflow.com/questions/tagged/javascript+php will give you all questions tagged with javascript and php.
The system I have allows tags with spaces in them, so the approach used here would not be a good fit for me.
What character would you use to separate the tags, so the URLs are still human readable, google readable and web browser compatible.
My gut feeling was to use commas. eg http://example.com/tagged/first+tag,second+tag
Any feedback or suggestions would be welcome.