10 Free Things to Do in Tokyo from Pingmag does just what it says on the tin: lays out ten free, fun things for a visitor to Tokyo to do in town, with an emphasis on geek pleasures like playing free video games and collecting digital photos of distinctive manhole-cover designs. For a classic of the Tokyo-on-no-dollars-a-day genre, see Justin Hall's "Justin Tokyo".
Depending on the season (peak time around hay-fever- and constant- cold- nose-running- months) you can spot people giving away free tissues with a little commercial message – almost everywhere. One of the most frequently distributed ones is the Takefuji-pack (yellow flowers – blue sky), which I even knew before I ever set foot in Japan.
Spotting the nice ones can be quite a challenge, besides some are only for women or men or young or old or Japanese only….. try your best and see what you can gather!