Yes, I let the odd one sit there, sometimes adjusting the stop-loss. If they're decently in profit, I sometimes choose a time to close them, near the NY close - I don't worry before that. I never leave anything open over the weekend, and rarely overnight. (For this thread I probably won't leave anything open overnight.)
My limit orders expire at 5.00 UK time, though - so my trades do have to open before the London close.
Wednesday 29th May
Cable: high 1.51294, low 1.51002
Long entry 1.51319, TP 1.51529, TS 21 pips
Short entry 1.50977, TP 1.50767, TS 21 pips
Euro: high 1.29624, low 1.29262
Long entry 1.29649, TP 1.29829, TS 18 pips
Short entry 1.29237, TP 1.29057, TS 18 pips