Doxory?

photon has decided External hard drive for data storage for graduate work. I'm using a MacBook Pro with Firewire and USB 2.0 ports.

Advisor bought a 2.5" one that's USB powered. Problem solved!

Asked 330 days ago

My choice: 2.5" with an enclosure that doesn't require an AC adapter

kyrandil
Cooler and easier.
lakmiseiru
Not requiring external power is very nice if you're using it for portable data storage.
Steve_p
I'm thinking the 2.5" since it sure makes you more mobile since you really only need one outlet rather than two.

jtu, perturbed, kevinr, jmorzins, paigep, coolworld, stupergenius, dzm, Aviendha1591, rasch, cshiley, nickolodean, glass_of_noodles, nelhage, avrilkiller, justjenine, jesse, escargonaut, ternus, Yoyo

3.5" with an enclosure that does require an AC adapter

Solus
the bigger ones have more space, and dont use much juice
geoff
sounds like the disk is stationary. go for the storage.

peggusus, wdaher, sauergeek

Skipped (with comments)

seph
the 3.5 will be faster. Not sure if that matters to you. You could also look at some NAS style thing.
trs
Which ever one is bigger?
hatter
It has to come down to budget - if you can afford a 2.5" drive with suitable specs (capacity, speed) then the portability will earn its price back quickly. If you can't justify from 50% price increase at the bottom end to complete inability to source the drive (>250GB, last I looked) then 3.5" it is.

If you make a stupid choice because a website tells you to, it's your own damn fault.