Is there anything wrong with creating a Python Pickle powered website?
In addition to the concurrency issues you are already aware of, you also must ensure that the file is always in a consistent state.  For example, if the server crashes in the middle of writing the file, what happens then?  It's a case you need to consider and implement a solution for if you go this route.
I have been toying with this idea for quite awhile now, but haven't seen any information on people doing it. I have a small website project where I need to load and modify 1 object. This object is pretty simple, and shouldn't be more than a few kb. Instead of running a DB for this small amount of data, why not just use pickle and/or shelve to save this data, and load it? I am planning on using a micro web framework like Bottle or Flask for the project.
Are there any reasons to not use this method to load the data? It will only load the pickle file at the time Apache starts up, so I don't think speed will be effected (faster than querying a db).
Thanks for any input!