

Challenging web application to improve web development skill set - sys_argv

I want to build a web application that will improve my overall web development skill set and that may possibly be put up on github and used in my portfolio. I have some experience in web development using Python(Django) and PHP. Apart from building a CMS, what kind of web application is technically challenging as well as suitably impressive?
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ainiriand
One good step forward would be building a web application that crunches a lot
of data from different sources and presents it in an original and practical
way. For example, something related to flights and hotels and airbnb.

