Githunt for Chrome
More About Githunt
You can look through the repositories for any technology of your liking and for any period of time. By default it shows the trending repositories (most starred repositories created in the given period of time) for the last week and as you keep scrolling, you will be presented with the popular repositories of the consecutive past weeks.
All you have to do is select how you would like to see the repositories (monthly, weekly or yearly) and the language, it will remember your choice and will show you the trending repositories in that category whenever you will open the new tab.