Palm pen

A pen comprising:

• a spherically shaped body;
• and
• an ink delivery system comprising:
• a tip having an end connected to the body and an opposite end comprising a nib;
• an ink conduit having an end coupled to the nib within the tip and an opposite end extending inside the body;
• a first ink cartridge fluidly coupled with the opposite end of the ink conduit and contained within the body;
• and
• a cartridge holder contained within the body and comprising a plurality of cartridge storage slots and an active cartridge slot, wherein the active cartridge slot is configured to hold the first ink cartridge, wherein the first ink cartridge is fluidly coupled with the opposite end of the ink conduit via the cartridge holder,
• wherein one of the plurality of cartridge storage slots is between the active cartridge slot and another of the plurality of cartridge storage slots.