Generate a unique ID based on the current time. Note: If you need a truly unique ID, use something like the JS Crypto API instead.

IDFromTime.js

// Both numbers and letters
function mixedID() {
  var now = new Date();
  
  timestamp = now.getFullYear().toString();
  timestamp += (now.getMonth < 9 ? '0' : '') + now.getMonth().toString();
  timestamp += ((now.getDate < 10) ? '0' : '') + now.getDate().toString();
  timestamp += now.getHours().toString();
  timestamp += now.getMinutes().toString();
  timestamp += now.getSeconds().toString();
  timestamp += now.getMilliseconds().toString();
  
  id = 'a';
  for (var i = 0; i < timestamp.length; i++) {
    id = id + String.fromCharCode(97 + Number(timestamp[i])) + (Number(timestamp[i]) + 5);
  }
  return id
}

// Letters
function baseID() {
  var now = new Date();

  timestamp = now.getFullYear().toString();
  timestamp += (now.getMonth < 9 ? '0' : '') + now.getMonth().toString();
  timestamp += ((now.getDate < 10) ? '0' : '') + now.getDate().toString();
  timestamp += now.getHours().toString();
  timestamp += now.getMinutes().toString();
  timestamp += now.getSeconds().toString();
  timestamp += now.getMilliseconds().toString();

  id = '';
  for (var i = 0; i < timestamp.length; i++) {
    id = id + String.fromCharCode(97 + Number(timestamp[i]));
  }
  return id
}

// Numbers
function numID() {
  var now = new Date();

  id = now.getFullYear().toString();
  id += (now.getMonth < 9 ? '0' : '') + now.getMonth().toString();
  id += ((now.getDate < 10) ? '0' : '') + now.getDate().toString();
  id += now.getHours().toString();
  id += now.getMinutes().toString();
  id += now.getSeconds().toString();
  id += now.getMilliseconds().toString();

  return Number(id)
}

Neat
What if two generations happen on the same ms? -> same id?
Differences with Ulid? KSUID?
Any boundary limits?