use Perl

#!/bin/bash
if [ -z "$1" ] ; then
   todo.pl --tag project-name list
else
   todo.pl --tag project-name "$@"
fi

that I install in the "bin" directory of my new projects. In this way, I'm able to track to-dos via this simple interface within the project ("project-name" above in the script is "rubrica" in the example below):

# List, by default
pinco@pallo /path/to/rubrica$ bin/todo
1H27 aggiungere le foto nella lista globale [rubrica]
1H35 verificare gli errori nella gestione delle pagine [rubrica]

# Todo set to "done"
pinco@pallo /path/to/rubrica$ bin/todo done 1h27
Finished task

# Task addition
pinco@pallo /path/to/rubrica$ bin/todo add 'verificare ordinamento per cognome'
Created task

# List (updated)
pinco@pallo /path/to/rubrica$ bin/todo
1H35 verificare gli errori nella gestione delle pagine [rubrica]
1KH7 verificare ordinamento per cognome [rubrica]

Update: I also added a little function into my .bashrc to automatically call the bin/todo script if available, or to call todo.pl if not.

function todo () {
    if [ -e 'bin/todo' ]; then
        bin/todo "$@";
    else
        todo.pl "$@";
    fi
}

In this way, when I'm inside the directory of one of my projects that have a bin/todo, this is what gets called. Otherwise, it is a simple proxy for the straight todo.pl script.

Update: I ended up getting rid of the script and adding a simple .todo-tags file where I need it. I also substitued the shell function with the following script:

#!/bin/bash

if [ -e '.todo-tags' ] ; then
   taglist=$(cat .todo-tags | sed 's/^/--tag /')
fi
echo todo.pl $taglist "$@"
todo.pl $taglist "$@"

In the .todo-tags all tags are on different lines and cannot have spaces, of course, but this works for me 100% of times.