On a non-single speed bike, rear cogs are pretty pricy, and when chain measure tool showing 1.0 it's probably already affected cogs. At 0.75 it's probably didn't affect the cogs yet. So it's preferable to change the chain before.
On a single speed bike it will not greatly affect cogs. Thou it sensible when riding and you should feel the ride better with new chain.
Personally, I don't use this tool, but a meter. As @kisp brought from wiki, if every 2 half-links equals 1 inch (20 half links are 10 inches), if those 2 half links become 2.56cm, it's up to change the chain. It's a bit hard to measure 2 half links, but when you take 20 it become easier. Yet, if you have a ruler with inches, it's very easy to measure 2 half links.

What does chain worn indicators 75% mean?
I'm trying to find an alternative to the standard tombstone qed symbol for more informal papers.
I initially thought of an empty square with Pub written inside, but what would actually be better would be a small beer mug symbol. (much like the one found in this set of icons http://dutchicon.com/iconsets/food-and-drinks-icons)

Unfortunately there doesn't seem to such a symbol in the comprehensive latex symbol list (although many funny symbols can be found there).
Has anyone thought about this? Is there any quick-and-dirty solution?
