Sublime Text 3 plugin - inline python evaluation.
For example you can write 3.14*0.6 and get the result (1.884) in your text. It also supports multiple selection.
Another feature is the use of $ as accumolation variable, e.g. having the following multipe selection:
will result with
arr[0 ] arr
arr[$+2] -> arr
To evaluate term, highlight and:
Super + Shift + X for Mac OS X
Ctrl + Shift + X for Windows/Linux