Hidden ship of the Think Tank, a small group of brilliant beings led by Kurros who offered to solve Voyager's problem in exchange for Seven of Nine.
The Think Tank ship was the vessel of a small group of highly intelligent beings who sold their problem-solving to anyone who could pay. It hid in subspace and contained a telepathic link that let its members think together.
In Think Tank, Voyager was hunted by Hazari bounty hunters, and the Think Tank's spokesman Kurros offered help in exchange for technology and Seven of Nine. Janeway discovered that the Think Tank had arranged the bounty itself to force a deal, and she turned the Hazari against the Think Tank instead.