Back in 99' heads was anxiously waiting for the release of Nas’ third album, I Am. Rumor was that It was supposed to be a double album until most of songs leaked onto the web, consequently sending Nas back to the studio to record new songs so the now, single CD would have fresh material.
One of the stand out joints from those series of leaks was Fetus (Belly Button Window). This was later released on The Lost Tapes however it had a slightly different beat arrangement and a few of the bars from the first verse were different. The original was more raw and way better.