In Mac OS X, use the following commands to format your large (no 4Gb limit) hard drive in FAT32.
It will be readable and writable on Linux, Mac OS X et Windows.
First, identify the disk you want to format with this command:
$ diskutil list
The output is going to look a bit like this:
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *232.9 Gi disk0
1: EFI 200.0 Mi disk0s1
2: Apple_HFS Mac_HD 39.9 Gi disk0s2
3: Apple_HFS Data 192.6 Gi disk0s3
/dev/disk1
#: TYPE NAME SIZE IDENTIFIER
0: FDisk_partition_scheme *1.9 Gi disk1
1: DOS_FAT_32 CORSAIR 1.9 Gi disk1s1
Let's assume we want to format the Corsair USB key and name it "Millenium Falcon":
$ diskutil partitionDisk /dev/disk1 MBRFormat "MS-DOS FAT32" "Millenium Falcon" 1.9G
For more info:
$ man diskutil