Doom 2000 was a hypothetical future project by id Software, rumors of which began to circulate on the Internet and in gaming press after a presentation by John Carmack at QuakeCon in 1998 in which he mentioned "Doom 2000" as an example of a future title that id might work on. The rumors were intensified and arguably given weight by the subsequent registering of a trademark for the phrase "DOOM 2000" and purchasing of the doom2000.com domain name by id Software shortly thereafter.
id Software employees downplayed the registration, however, stating:
The first half of 2000 subsequently came and went without any news of a new Doom game, until Carmack's subsequent official announcement of a new project in June 2000. Due to the lack of a working title specified in this announcement, it led to further speculation that it would be the earlier-mentioned Doom 2000, but by the following E3, it was announced that the new game was to be titled "Doom 3," putting the rumor to rest for good.
No products or games by id Software ever subsequently used the trademark, and the domain name remained parked for years without a functioning website attached to it. The registration was eventually allowed to expire.