On Day 4, in St. Francis Hospital, on your first visit in the room where you meet a nurse and a patient (just the room above the entrance), check behind the cabinet on the upper part on the room. You'll get a Trading Card, but if you keep checking you still get more Trading Cards. You can get how many Trading Cards you want. But this only works once.
4/13/2005
Chocobo Flag
On the City Map, Select the Natural History Museum. When the Helicopter starts circling, you can see the big blue banner hanging from the museum has a silouette of a Chocobo and says "Chocobo" under the picture!
8/24/2005
Parasite Energy Regeneration
When you use your Parasite Energies in battle, your PE gauge will eventually stop charging altogether, preventing you from using PEs for the rest of the battle. However, if you switch your equipped armor during battle, it will restore your PE regeneration rate to its original amount, even if it had previously stopped. Therefore, if your PE gauge is charging too slowly, or stops charging, just switch your armor while in battle to restart the regeneration. This is a handy trick against stronger enemies and bosses, where your Parasite Energies are essential to victory.