Originally Valve was going to port Half-Life onto the Dreamcast console in the early 2000s. The Dreamcast version was planned to have many Dreamcast references to Half-Life.
By breaking open one of the crates with the tech parts would unveil the games Dreamcast disc. In early builds of the game in the japanese version the discs were replaced by Sonic Adventure discs. The crates would also unveil Dreamcast VMU's (Virtual Memory Unit) with other tools as well.