Infinite Speed

Infinite Speed is a glitch that can be performed in Metroid Prime 2: Echoes (Nintendo GameCube version only). This glitch involves use of Secret Worlds and allows Samus to avoid her first encounter with Dark Samus in Hive Chamber B and therefore retain her Missile Launcher, Bombs, Space Jump Boots, Boost Ball and Spider Ball past the point where she would lose them to the Ing. Although the game mentions Samus losing the Grapple Beam and Power Bombs, neither item is usable prior to the theft.

Instructions
The glitch has a high likelihood of crashing the game, forcing the player to try again.

The player must play through the game as normal until they reach the Hive Tunnel. Once there, they must open the door to Hive Chamber A and carefully stand in the corner just outside the door, but they must make sure the onscreen Map does not change from Hive Tunnel. Samus must point at a Heavy Galactic Federation Crate and board with holoscreens and then enter Morph Ball mode. The player must hold down right. If the glitch was performed correctly, the Morph Ball should be stuck in the wall and rolling rapidly, before slowing down and ultimately stopping.

Next, the player must wait for 50 seconds until the Morph Ball glows white. If Samus unmorphs at this point, the glitch will be cancelled. She must Boost from the wall once, and then roll over to the cobweb in Hive Tunnel to unload Hive Chamber A. The Morph Ball is noticeably faster, and if Samus is hit choppy red lines will appear on-screen, possibly representing hitboxes.

Continuing on, Samus must roll in between a small and heavy GF crate. The player must hold down the analog stick slightly and then charge and release a partial Boost. The screen should go black. If nothing happened when the crates were destroyed, the player can try other crates in the room.

If this was successful, Samus will be in a Secret World outside the boundaries of Hive Access Tunnel. She can move under the violet Translator Door. Those with experience in Secret Worlds can simply jump up to the door to Hive Transport Area, although inexperienced players will need to "float" upwards. However, this is very slow and takes approximately twelve minutes.

Regardless of how they get to the door, the player must shoot it to load the room and then jump down to the elevator area. To get back in bounds, they can have Samus scan the Interface Module for the elevator. Interestingly, if Samus enters Hive Chamber C, the Dark Troopers will not react to her presence.

Returning to the Chamber as normal after all bosses have been killed causes Samus to lose her abilities, and render the game unplayable as there is no possible way to recover the items.

A link to a video showing the glitch being performed can be viewed here:

Trivia

 * A similar glitch can be performed in Metroid Prime in Connection Elevator to Deck Alpha. However, this glitch only allows Samus to keep her items as she leaves the Frigate Orpheon. She will still lose her abilities after landing on Tallon IV.