Easy Reference Sheets - Scotland - Western England & Wales - Eastern England - Summary sheets with paddling speed calculators, wind speed chart, CG contact & MSI Broadcast Times, Marine VHF channels - (.PDF)
Falls of Lora - discussion
Maps overlaid with tidal data - Ricb250 produced this excellent resource. Click into the relevant area until the tidal stream info appears.
Moon Phases - useful for trip planning.
Tidal constants relative to Dover from SeaAngler.com - the free booklet from Marinecall Weather Services is also worth having as it gives tide times for Dover, Plymouth and Portsmouth together with constants for 70 ports round UK.
Tidal flows - Rule of 3rds - useful Fact Sheet from Cailean MacLeod. (.PDF)
Tidal Planning - useful Fact Sheet from Cailean MacLeod. (.PDF)
Tidal Planning Matrix - handy worksheet to help in working out tides from Cailean MacLeod. (.PDF)
Tides, Inshore Waters & Shipping Forecast, MSI Broadcast Times, Surf and Synoptic charts - Synopsis of useful resources, all in one location.
Tidal planning - paddling speed - see this excellent work by Julian Patrick on calculating time, taking tide into account which includes downloads for his "crib sheet" and Anglesey tidal constants.
Understanding tides - UKDivers.net has an excellent article explaining how tides work. Also includes moon phases and "Rule of 12ths". Their description and diagram of why there are two tides daily may be a little inaccurate - the description here is possibly more plausible. See also this discussion on "unusual" tides. This article by Phil Clegg provides a broad overview of how tides work, and factors to take account of including explanations of the various "rules".