When you try to enter office's multi-level parking but your access key doesn't work.

When the Director/VP/Head says "even though the market has turned, we have _no_ plans to lay people off"

When you receive a notification that your <enter company's source control> privileges have been revoked.

When you see a voicemail (or tweet in case of Twitter) from HR around Friday afternoon/evening or early Monday morning.

When you apply for vacation but the request is denied for unspecified reasons ("We may need you here during that period").

When your manager keeps postponing your ++year() roadmap meeting requests.