Filesystem            Size  Used Avail Use% Mounted on
/dev/sda1             9.4G  6.6G  2.4G  74% /

find / -type f -size +50M -exec ls -alh {} \; | awk '{print $9 ": " $5 }'

/usr/src/linux-source-3.0.0.tar.bz2: 73M
/proc/kcore: 1018M
/home/user/important.file: 1.9G