Publicly available webservice I can use

I am learning to write PHP client programs which call webservices with POST & GET. Is there any publicly available webservice I can use for trying out client programs? Basically, I don't want to get into writing a webservice first before I sta开发者_运维知识库rt trying out client programs - are there any such easy to use webservices I can use?

You can browse through ProgrammableWeb's API directory (REST protocol). What kind of webservice are you looking for in particular?