BTW Don't clone a successful product. Have some respect for yourself and for others. It rarely works anyway (struggling to think of a single case where it has).
I am using a service called Invoicely for recurring invoices in my small business. One day I randomly googled for some of its features and found a post of a guy who claimed (and I believe him) that Invoicely is a blatant screen-by-screen clone of their own SaaS.
I felt really bad for that guy, and after some time I thought that it's a good idea to switch to them. The problem: their website name is so difficult to remember, I never got around to actually opening an account there.
Some shifty guys literally copied an existing service up to their Javascript and CSS, and improved it dramatically just by giving it a name I can remember.
You mean, like gas stations?
I used vk.com a lot in the past and in terms of UI it was much more convenient for me than Facebook.
Same ideas, different implementations.
I'm talking about people who just rip-off someone else's design with adding anything original.