DynaBlocks is one of three names that were considered for Roblox during its early development. Contrary to popular belief, it was not a former name for Roblox. Jim Stevens registered this site on December 12, 2003.
It was then later scrapped in favor of Roblox in early 2004, due to DynaBlocks being "too hard" to remember. dynablocks.com, dynablox.com, and dynablock.com all used to redirect to roblox.com, and "Waiting for www.roblox.com" appeared at the bottom of the screen. As of 2020, the links no longer work
The earliest form of the website that can be accessed is here. It can sometimes fail to load.
The recreation shown here shows what the website may have looked like.
At BLOXcon 2013, during the "State of ROBLOXia" presentation by CEO David.baszucki, an early mockup of the DynaBlocks website was shown. Oddly enough, it includes a reference to GoBlocks as well, further confirming that GoBlocks, DynaBlocks, and Roblox were the three names that were considered.