
The old Percy Abbott 'Squash' Glass vanish could be useful. In this you throw the shot glass up into the air and is vanishes. Miles Sinclair at Magicial Wonders still sells it but under another name as the Vanishing Glass. It is still a plastic shot glass. The gimmick which you could make (pm me) is also useful as a hidden holder.
I can tell you of a very simple way of holding 1 or 2 of those 'longish sherry( full) glasses' (pm me)
There is the production of a half pint glass full of liquid. You pull off your coat, turning it inside out and there you have the full glass.
And what about the Healed & Sealed Coke tin? Very visual.
I'm sure Davenports will still sell the Wine Glass Production holder.about £1:50
There's the Splash Bottle (Burst a balloon and there's a champagne Bottle) at £28 Often done close up.
The Invisible Stopper. Bottle with liquid. It doesn't run out. Matchsticks pushed up inside and the liquid stays. It runs out when you wish. £1:50
Universal Floating Gimmick at £3. Float a glass a cup etc.
The as a barman carries a pen. The Pen Thru Anything.
Slush Powder. And the Slush powder book by Gabe Fajuri at £3
The Glorpy ( Haunted Handkerchief) adapted to a bar napkin.
Torn & restored paper napkin.
Any tricks with notes/bills
Check out Tom Mullica..The magic barman
At around £6 Check out Karl Fulves Self Working books( especially Table Magic) and Martin Gardner's 'Table Magic. There is also his Encylopedia of Impromptu Magic. I think this immense work is soon due out on CD
You have a natural servante or lapping place with a bar.
Allen Tipton

Began magic at 9 in 1942. Joined Staffs M.S at 13. Nottm.Guild of M. (8 times President. Prog Director 20years)IBM. Awarded Magician of Month 1980 By Intern. Pres. IBM for reproducing Dante's Sim Sala Bim. Writes Dear Magician column for Abra. Mag.