If you are a fan of minimalist decor and modern furniture, you will love Friend in Hayes Valley. They sell all types of home accessories and furniture from well known and innovative designers. This is a great place to shop for gifts though items can be on the pricey side. Very cool clocks and lamps, especially. Go during their holiday sales and you'll see many items on sale for 50% off.
Check out their online shop if you can't make it to the store: http://store.shop-friend-sf.com/