Hell, I’m constantly pondering, B… 
I wasn’t around for a while, so I missed that…Thanks for bringing it to my attention, because now ya’ got me cogitating…(That’s what happens when you give cerebral stimulation to an inveterate ‘ponder-er’… 
)
That’s pretty cute! 
Hi andreseloy, i don’t understand all the replies, but to make mask with current alpha you must do the following:
An object must be in edit mode.
Press CTRL and click OUTSIDE the object, now you can drag your alpha as mask.
Other hint:
CTRL+ALT on model: erase mask
CTRL+ALT outside model: draw inverted mask (erase mask with current alpha shape)
Hope this helps…and i’m not wrong 
cameyo
I want to thanks all the reply that has been made and the didactical discussion that has been generate that allow me to revisited in the Quicklink all the tutorials or topic related with Alpha.
Cameyo: YOUR POINT IS CRITICAL: CTRL+DRAW+OUTSIDE IS WHAT ALLOW ME TO DO WHAT I WAS ASKING¡¡¡¡¡ IN THAT WAY I CAN MANIPULATE A MASK PREVIOUSLY DONE ONTO MY ACTIVE EDITING OBJECT,
Thanks very much to all of you that has take your time and be patient in explaining this related topic.¡¡¡¡
Thanks CAMEYO at least in the review I made yesterday night that point CTRL+DRAW OUTSIDE was not evident to me.¡¡¡
1.-ps: Bonecradle, when you made your fantastic tut morph masking I was trying to exercise with it but I really didnt understand to much about UV mapping and Nº poligon and so on…and became confused (not your tut but my poor background)but probably now I could use in the excelent way you have do it¡¡
2.- What means that terms?
pondering
cogitanting
Is a sort of combustion?