In 2365, Jax DeSabel and Sam Lator became acting ensigns, and were sent on a mission to the 20th century, Earth, to gather data on a number of things, primarily the atmosphere at the time. While they were there, they each designed and built an AI. Jax called his Boulder, and Sam called his Nuggit.
Boulder was slightly larger than Nuggit, though both were fairly small. Or to be more precise, their robotic bodies (modeled after toys of the time, and of the same names as the two AI's) were small. It is important, ultimately, not to confuse Bole and Nug with their robotic bodies. They are their intelligence. They do not always use their bodies. They can upload or download themselves into any computer or computer system, or into other electronic systems, devices, or robotic bodies. They could put themselves into an android if they wanted to do. Normally they are seen in their robotic bodies, but they're not limited to them.
When Sam and Jax finished their mission, which they conducted from 1985-1990, but which took them about 2 years of their own time, they entered Starfleet Academy. After that, Bole and Nug visited them from time to time, but spent a lot of time on their own, having their own adventures (of which they told only a small portion to their friends Sam and Jax). It was at some point during the 2 years when Sam and Jax were at the Academy that Nuggit and Boulder acquired their small ship, which they called the Colossus. It was smaller than a shuttlecraft, but more than enough room for the small AI's. It could, when necessary, accomodate a few humanoids- after all, it had originally been humanoids who owned the ship.
The Colossus was obviously originally of Ferengi design, though it was also obvious that it had had a few owners since it was built, not all of them Ferengi. Each owner had added their own modifications, and Bole and Nug were no exception. By the time they were finished with it, it was despite its size (and to an extent because of it) about the best ship in the quadrant. Boulder and Nuggit have not as yet told Sam and Jax the story of how they came by the ship, or what it was called when they bought it (but hey, i'll tell you- it was the Scarab; maybe i'll write that story someday).
It was destroyed in 2375, during a fight in Mirror Gamma just outside the wormhole, by a fleet of Alliance ships, including a huge Klingon vessel called the Primus, akin to the one commanded by Worf's double. After the destruction of the Colossus, they acquired a Klingon vessel, still small but considerably larger than the Colossus, which they called the cha'DIch.
While Boulder takes after Jax as an engineer, Nuggit takes after Sam as an engineer and scientist. Also, both AI's are extremely good hackers, as well as explorers, adventurers, and businessbeings (particularly illicit business). They are quite good at obtaining contraband items for themselves and for resale. They do, however, possess some of the moral values held by Jax and Sam. In any war, they will likely be on the side of the Federation, although they of course have leanings toward organizations such as the Maquis, as well as having friends in the Gamma quadrant who oppose the Dominion.
In 2377, they acquired new regular robotic bodies, which were droids from the Star Wars galaxy, modified with technologies from this galaxy.
Boulder isn't really a bad guy. He has his fun. He likes his friends, even if he doesn't always act like it. But he is too easily annoyed or angered. He is quick to yell, to insult, to just generally rant. But he's not always like that.
Nuggit is more calm and even-tempered than Boulder, and somewhat more logical. He can certainly be more diplomatic. He usually allows his friend Boulder to assume the dominant role in their partnership, but ultimately, they are equal partners.
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the basis of Boulder's new body
This is Bollux and Blue Max, taken from Star Wars: The Essential Guide to Characters. Pay no attention to Blue Max (the droid in the humanoid droid's chest); he's not part of Bole's new body. Rather, Thirteen might stay in there occasionally in Bole's old body. Otherwise the space can be used for storage or what have you. In addition to the Star Wars droid (which in The Original Continuity would have been acquired from an Imperial starship, but in the new continuity that as of this writing hasn't yet been started, i think it may come from plans in the Century Bat's computers) this new body has Federation technology, in particular a positronic brain akin to Data's; and Borg technology. But anyway, I haven't been able to draw out plans for this yet, so the droid will suffice for now. Actually, his body would be a somewhat more advanced model (BLX-9) than Bollux (BLX-5) was...
In 2286, on Memory Prime, Pathfinders Eight and Ten co-wrote a new Pathfinder, which they called Thirteen. Thirteen lived there an awful long time, and eventually got bored.
In 2365, Jax DeSabel went to 20th century Earth, where in 1988 he read a book called "Memory Prime." The book inspired him to create Boulder. On a trip home to his own time, he put in an application to interface with the Pathfinders.
In 2367, on his last trip home before completing his mission in the 20th century, his turn came up to speak with a Pathfinder. He went to Memory Prime, where he made the acquaintance of Thirteen, who told Jax he wanted to explore what the Pathfinders call Datawell (the world outside the database on Memory Prime, which I believe the Pathfinders call Transition). Jax told him that if the opportunity ever presented itself, he would try to help Thirteen out. Boulder was also with Jax on this visit, and also met Thirteen, and even temporarily downloaded himself into Transition, where he learned to think at the advanced rate of the Pathfinders. He would try that sort of thing in his own robotic body and other computer systems in the future, but most of the time he liked to think at a rate closer to that of humans, so as not to get bored incredibly quickly. He also promised to help Thirteen if ever he could.
In 2377, Boulder created a new body for himself, and gave his old one to Thirteen. Thirteen left Memory Prime with Boulder, and spent a time directing the efforts of nanites and exocomps in the mirror universe, who were helping construct a fleet of ships based on designs from the computer records of the Century Bat. Later, he left again with Boulder and Nuggit, but eventually he would want to get his own ship and go off on his own...