A little-known feature of NTFS on Windows 2000 and later is sparse files. A sparse file is a file with a section marked as being null. Under NTFS, this results in no space being allocated for the marked section. This can results in a large file occuping as little as 128 kilobytes of disk space.
The Faker creates sparse files.
The Faker is a powerful tool, use it with care. Not all programs understand sparse files. Some will refuse to open your 20 gigabyte fake file. Many will attempt to open it, and choke upon the Faker's creation. Few are capable of succeeding.
The upper limit for a sparse file is currently unknown. The true size will only be shown if you look at the file properties.
The Faker can only create sparse files that have integer sizes. Should you try to create a 20.3 gigabyte fake file, the Faker will look down upon your pitiful attempt.
The Faker works on Windows 2000. Do not offend the Faker by using an inferior system.
The linked code (faker.zip) is public domain and may be used for any purpose. No warranty at all. May contain nuts. 99.9% empty space.