Capturing ideas everywhere

In one of the last posts we have been talking a little bit about how to handle the multiple tasks effectively by using mindmapping.
Similar concept to GTD (Get the Things Done) but of my own.
One of the topics whenever you want to use mindmapping to control your work is how to capture the multiple ideas that are constantly popping up.
This issue turns out quite easy when you are at the office, just get another new branch in your map and you write it down. What does it happen when you are outside "on the field"?
I am not a proud owner of a mindmapping-inside application portable device, so I attack this problem by using "notes writing" applications on my handy (if I´ve got enought time) or just by dictating the note to the recorder application.
Whenever I came back to the office, I look and listen to my handy and put the different news taks, notes, ideas, links, phone calls reminders... into the mindmapping.
I have also added a new branch to my Activities Framework map, named Rather Urgent Issue, to attach these notes in case they were urgent.