depends on your definition of "webserver", there are plenty of examples where a simple script builds a HTTP connection via a dedicated port, i.e. w/o a "standard webserver" like apache.

Best known example are pod servers.

EDIT: The problem is rather to automatically launch a browser/ open a new tab when you start your script . Otherwise the user hast to connect manually to a dedicated port.

UPDATE:

typical usecase

lanx@nc10-ubuntu:~$  podwebserver 
I am process 8706 = perl Pod::Webserver v3.05
 Indexing all of @INC -- this might take a minute.
...
 Done scanning @INC
You can now open your browser to http://localhost:8020/
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