This is fun. I remember our fumble chart with my group in high school (and a few others during college)...or the gist of it. No fun those 1's.
It is entirely possible this came from some old source (I see a list from Dragon being mentioned a few times) but I don't know if it did.
Also, this not exact (it was , but you'll get the idea.
1- Double Fumble- In an incomprehensible series of never before seen mishaps, you behead yourself.
2- Dismemberment: left leg, from hip
3- Dismemberment: right leg, from hip
4- Weapon dropped: in reach, attack next round
5- Weapon dropped: out of reach, spend next round retrieving weapon
6- Dismemberment: left arm, from shoulder
7- Dismemberment: right arm, from shoulder
8- Weapon dropped: in reach, roll/take normal damage
9- Weapon dropped: out of reach, roll/take normal damage
10- Weapon dropped: out of reach, take normal damage, weapon broken
11- Dismemeberment: right leg, from knee
12- Dismemeberment: left leg, from knee
13- Weapon dropped: out of reach, roll damage (with bonuses) on nearest ally
14- Weapon dropped: out of reach, roll damage on adjacent enemy
15- Dismemberment: right arm, from elbow
16- Dismemberment: left arm, from elbow
17- Weapon broken. No one takes damage, but weapon is useless.
18- Hit ally, roll full damage (incl. all bonuses). Weapon is not dropped.
19- Hit yourself, roll full damage...and double it (effectively a nat. 20 on yourself)
20- Natural 20! Cancels out the Fumble. Attack as normal next round.