i have one of these and like it a lot...holds a lotta gear, but there are no internal pockets so i end up with a lot of 'bags inside a bag'
Watershed Westwater Backpack Yellow
i like these a lot too:
GILL Full-Finger Pro Racer Gloves at West Marine
i keep the vion mini compass, handheld gps, snacks (nuts/fruit), small first aid kit, leatherman, knife,xtra clothing depending on the weather, sport towel (the mini super absorbent kind),hat,handheld vhf,sunblock...
when you are buying this stuff, you might want to consider how often you are going to use it. ie, on my boat ive got extra gloves for guests. if you are going out for a visit, a backpack you already have would work, some clothes, a bit of food and a good attitude would probably suffice.