moving apps to an external HDD

[sunsnewmac]

I posted a few days ago about deleting some apps to save space on the HDD.
I was wondering if this makes sense: dumping a few of the iLife apps that I don't use onto an external HDD rather than deleting them completely. I know I can reinstall them using the Apple startup disks, but if they are on the external drive can't I run them from there if I chose to? Or do they run best when on the same HDD as the OS?

 

[mad jew]

I always think it's a good idea to keep 'em together on the boot drive so that I'm sure Software Update can find them. They're not particularly large in the scheme of things so there must be other data you can transfer across to the external assuming you're low on space.