Interstellar Trade

Although nanofabrication and solar system and habitat cluster resource self-sufficiency greatly reduces the amount of trade required by wormhole link or (for more isolated systems) relativistic trader, interstellar trade still remains an important part of galactic civilization

Primary items that are traded are almost always those things that can not simply have their designs sent over a commlink. These include:

1) Transapient design/comm templates:

For all of its tremendous bandwidth, the Known Net still finds its resources strained (or even exceeded) when attempting to transmit information of sufficiently high transapient or deity class. Godtech devices are often be so complex that while there are storage devices able to hold the blueprints, there is insufficient bandwidth to transmit them. Instead the storage devices have to be physically transported to their destinations where sufficient processing power has been constructed to translate the blueprint into hardware.

In a similar vein, consider how much bandwidth a deep, involved conversation between two gods takes up! The thoughts and communications of the Archai are often so vast and involved, so complex that they have to be transported in a manner similar to design blueprints. An ancient historical low tech analogy from industrial age Old Earth was sending a letter across the Atlantic in the days of steamships and telegraph. But in this case the letter may actually contain a copy of a portion of each correspondents mind. And the minds are bigger than many planets.

2) Luxury or one-of-a-kind items.

Actually, these are not infrequently one and the same. In a future in which any material object can be mass produced at whim unique or one of a kind items (artwork, handicrafts, etc.) often take on enormous value. Of course each item has to be authenticated and certified as a unique original. The same applies to items made 'by hand' rather than simply mass replicated using nano. And again to items of information made one off (music, poetry, literature, all targeted to just one person, or carrying the 'chic- factor' of only one or a limited number being guaranteed to exist). Such information might not be able to be transmitted over the web even if the storage medium itself is not part of the value (and it probably would be, consider rare hardcopy books) due to security concerns (Cyberian hackers, ahuman or other non-sephirotic ai sniffer probes, and so on).

Finally, even items that can be mass produced using nano can take on additional, and very great, value if certified as actually coming from an original source instead of a replicator.

'Here, try this wine. Its actually original from the Valles Marinaris vineyards. Bottled on Mars and shipped here and everything. Doesn't it just taste so much better than that replicated stuff?'

In these cases the 'value' of these items would be in people's heads, but that has been the case with trade in luxury items for all of human history. A citizen of the galaxy, or anyone else, may not actually need any of them. But they sure may want them.