1. Something I affectionately call: 'Stop punching yourself':
Though the title may imply humor, this strategy is far from funny. In instances where, let's say, I have a gun leveled at my person, it has been a useful, though odd looking, use of Arms of the Abyss to have an Arm originate from the shadow within the target's nostril, attach itself to the subject's wrist, and then yank the hand upward into the target's face, via the nose. This is even more effective when imbibing said Arm with high levels of Potence. Not only does this strategy cause damage to the target, but for a time, renders one of his limbs immobile. It is also quite useful to apply this trick to both hands at once, so as to cause damage, immobilize, and obscure the subject's vision.
(A useful variant on this is to have the Arm attach itself to another target's neck, should a threat be in a pair, and bring the two's skulls crashing together)

2. Discreet Communication:
At times, it is useful to be able to transmit information across short distances to an ally on the spur of the moment, rather than wait for a 'private' moment at an inconvenient later time. To combat such instances, I've found it is quite valuable to manipulate shadows into silent
messages.
With careful concentration, using the basic talent of Shadow Play, one can stretch shadows into coherent text, say on a wall, or on the back of someone's hand. I cannot count the times when having a silent means of communication has served me well in both social, and combat situations. It is especially useful when in Tenebrous form, which makes absent our use of verbal speech.

3. 'Watch out for that first step...'
Though requiring a great deal of Mastery, I have found quite a useful application for Shadowstep, beyond the obvious advantages of travel and stealth. Rather than the long explanation, I'll relay the short story:
It was my experience to engage an opponent in the enclosed top floor of a tall skyscraper (the Blue Bloods 'do' love their Ivory Towers). Rather than a long, drug out confrontation, I simply pulled him to my person with an Arm, and 'Stepped' through to a shadow just outside the window on the top floor with him in my grip. It was quite amusing, watching the Ventrue fall those 40 stories as I took the time in free-fall to assume a Tenebrous form. While gravity pulled my opponent down into quite the messy smear on the pavement, my incorporeal form simply 'splashed' to earth, were I reformed, sucked the unfortunate puppet of the Antediluvians dry, and went on my way.

So, there are a few ways in which to further your use of our dark power, childe. But, don't presume I'd be so foolish to reveal all I know. What's that? Can't speak? Oh. Shadow got your tongue?