Months ago I got a Macbook Air with Mac OS X Yosemite installed.
Mac OS X comes with an wide range of fonts for all languages and scripts. For example they came up with several cool Bengali fonts which renders far better than Windows or Linux fonts. (Windows fonts suck btw).
When I work with web projects, or writing with Pages or other apps, I had to go through a huge list of unnecessary fonts. For example, fonts for Arabic, China, Korean, Hindi, Myanmar, Tamil, Telugu etc are totally unnecessary for me. So I opened the app Font Book and selected which fonts to remove. Then I manually "rm -rf"ed the fonts. Here is the list of fonts I removed.
rm -rf /Library/Application\ Support/Fonts/ヒラギノ* rm -rf /Library/Application\ Support/Fonts/儷* rm -rf /Library/Application\ Support/Fonts/华* rm -rf /Library/Fonts/AppleGothic.ttf rm -rf /Library/Fonts/AppleMyungjo.ttf rm -rf /Library/Fonts/AppleSDGothicNeo-* rm -rf /Library/Fonts/Baoli.ttc rm -rf /Library/Fonts/Han* rm -rf /Library/Fonts/Hei* rm -rf /Library/Fonts/Hiragino* rm -rf /Library/Fonts/Kaiti.ttc rm -rf /Library/Fonts/Lantinghei.ttc rm -rf /Library/Fonts/Libian.ttc rm -rf /Library/Fonts/Malayalam* rm -rf /Library/Fonts/Myanmar* rm -rf /Library/Fonts/NISC18030.ttf rm -rf /Library/Fonts/Nanum* rm -rf /Library/Fonts/NewPeninimMT.ttc rm -rf /Library/Fonts/Oriya* rm -rf /Library/Fonts/Osaka* rm -rf /Library/Fonts/PCmyoungjo.ttf rm -rf /Library/Fonts/PT* rm -rf /Library/Fonts/Pilgiche.ttf rm -rf /Library/Fonts/STIX* rm -rf /Library/Fonts/Sathu.ttf rm -rf /Library/Fonts/Silom.ttf rm -rf /Library/Fonts/Sinhala* rm -rf /Library/Fonts/Songti.ttc rm -rf /Library/Fonts/SukhumvitSet.ttc rm -rf /Library/Fonts/Tamil* rm -rf /Library/Fonts/Telugu* rm -rf /Library/Fonts/Wawa* rm -rf /Library/Fonts/Weibei* rm -rf /Library/Fonts/Xingkai.ttc rm -rf /Library/Fonts/Yu* rm -rf /System/Library/Fonts/HiraKakuInterface* rm -rf /System/Library/Fonts/STHeiti* rm -rf /System/Library/Fonts/ヒ*
But wait, if you are willing to do so, do on your own risk. It might show errors while upgrading OS X if you remove core Apple components.