What creature or vehicle has the fastest speed without any magical or psionic effects, and without any feats or items, AND without any templates or class levels, in 3.5 D&D? In short, no modifications of any kind. Just looking for something published as-is that I can point to.
Within the SRD, there are epic dragons, capable of 350 ft/rnd movement (the wyrm and great wyrm force and prismatic dragons are all capable of this speed). Although, a blink dog can beat its double move speed (720 ft. dimension door as a free action supernatural action, followed by a double move of 80 ft. for 800 ft.). An epic dragon can move 700 ft as a double action, or 1400 feet as a run action. The blink dog can run after a dimension door for a total of 880 ft. of movement (or 920 ft. if you allow it to use the run feat, which the base creature is shown to have). Either way, it is slower than an epic dragon taking the run action while flying.
If you wish to look beyond the SRD, I believe you are still going to need magic to beat that speed. Once you allow magic, Spelljammer ships can reach speeds of 1/161 the speed of light, but they are listed as having that speed as their base maximum when you allow magic (called Cruising Speed).