Space...I need Space!

Freeing up space in Mac OS X and OS X

 

Another thing that takes up space that you might not realise is your downloads folder and trash. Over time they accumulate a bunch of files. I just trash the contents of my downloads folder immediately and I empty my trash once a week (I wait to make sure I don't need something again).

In addition to the tips in the link above (which is a very good resource), I would suggest carrying around a slim external hard drive for your extra files and such. The Western Digital Passport series drives are pretty slim with a decent amount of storage. Or you could just get a bigger SSD. OWC sells some, but they are a bit pricey. I would probably wait a bit until the price goes down.

 

A 64 GB micro sd card and a nifty minidrive would give you 64 gb for less than $100.

http://www.kickstarter.com/projects/1342319572/the-nifty-minidrive

 

If you have a 13" MacBook Air you could get a SD card and permanently leave it in the SD card slot for up to 64GB worth of extra storage