"src". Takes the name of a variable (usually a function) and searches my source directory for definitions of that variable. The way it recognizes definitions is fairly ad-hoc (it recognizes "def", "mac", "defmemo", and a few others; it doesn't attempt to recognize forms like "(let x 2 (def ...))").

  arc> src.src
  From: /Users/waterhouse/Dropbox/arc3.1/a
  (mac src (name (o strict t))
    `(src-fn ',name
             ',strict))
  Found 1 results in 1 different files.

"aps". Apropos; derived from the Common Lisp function. Returns all bound variable names of which the supplied argument is a substring.

  arc> aps.mat-
  (fermat-prime mat-add mat-add-mod mat-det mat-det2 mat-expt mat-id
  mat-mod-expt mat-mul mat-mul-mod mat-order mat-trans)