Where is best place to find sources of standard linux command line tools?

Into: I like learning by reading sources. But it's tiring of searching them across internet splited on many many different project sites. I'd love to see **central browsable** repo with sources of many many apps in one place. - When someone want to find documentation of some Linux tool, best place is : man toolname. - When I want to browse Linux sources "on-demand" I can always jump to : [Linux Cross Reference](http://lxr.free-electrons.com/) . - When I want to find most common staff, I can find all sources in [Coreutils](http://www.gnu.org/software/coreutils/) . - When I want to check how to build something, I can (for example) jump into http://www.archlinux.org/packages/ , check it's pkgbuild. Is there any repo that holds sources of most of tools in one place ? - just like man holds documentation or [Linux Cross Reference](http://lxr.free-electrons.com/) kernel sources. I mean something for "rapid" "on-demand" checking how stuff is implemented. (Yes, I know google -> but I am tired of routine: 1. searching project site 2. browsing repo or even worse -> checking out it's repo 3. deleting when finished) **REMARK:** I've stressed out, I'd like to check tools : rapidly, fast, on-demand. It means: I don't want to install whole app with it's sources just to take a look into it's sources. (btw. web resource is preferable, so I could check sources from many computers - I do not have admin on all of them)