how do you guys save your old editing jobs? (just incase you wanted to go back to them in the future for a small adjustment and not have to re-edit the entire vid)

i just finished editing my first complete vid (YAY!!) and i have to empty up some room on my comp to start editing the next vid (the current captured vid clips are taking up about 10 gigs of space). if i delete the raw captured vid clips (that Vegas 5.0 used for this editing job) and the Vegas file itself, i'll lose all that editing info that i spend days on.

What do you guys do? Any recommendations?

Thanks!!