I have recently been experimenting with 1NT openings that aren't the classic 4333, 4432 and 5332 patterns with some success. I have found that many 5422 patterns are often best handled with a 1NT opening, and even some 6322 hands with a long minor are good 1NT openings. Here is an example from a recent club game.
As dealer I held the following hand:
This hand has a difficult rebid if it is opened 1 Club and partner responds 1 Spade. It is too strong to rebid 1NT or 2 Clubs. It isn't strong enough to reverse with 2 Hearts. The value bid, 3 Clubs, is awkward as it suppresses a good heart suit. So I opened it 1NT. Jenn bid 2 Clubs, Stayman, I showed my heart suit, she invited with 2 Spades, showing 4 spades and invitationl values, and I accepted with 3NT since I had such a nice source of tricks. (Note: Jenn and I have an agreement that with both majors, we show hearts first. So she can invite with 2 Spades since I might have both majors. If she invites instead with 2NT, she is denying 4 spades.)
LHO led a small diamond, and I looked at:
RHO played the ten of diamonds and I won with the queen. Now, if LHO has the ace of diamonds, likely given the lead, I was a favorite as I could see 5 clubs, 2 hearts and 2 diamonds for my 9 tricks. The opponents would have to cash out 4 spade tricks without blocking the suit, which isn't easy with this holding in dummy. So I led a diamond at trick 2 to LHO's ace. LHO actually shifted to a heart, so the hand was over as I quickly claimed my 9 tricks for a good score.