Be Unreasonable
It's really useful to be unreasonable.
When you have a large task ahead of you, try asking yourself some odd questions. Like, "what if I finished it in 1/10th of the time?" or "what it got 100x more users than anticipated?".
Start with "crazy ideas" and "unrealistic expectations", and then play around for a bit! By working backwards from unreasonable demands, you'll devise bolder schemes!