So, you are attending a startup weekend? You will be crammed in a room with strangers to collaborate on an idea-maybe even yours? I have some advice for you to improve your output during this 54 hours.
Use Google Drive to work on concept documents, texts, spreadsheets for your business plan and the presentation. Everyone can work on every document at the same time and all collaborators will see updates in real time. Don't even try to work with files during the weekend.
If you need to share files, use Bittorrent Sync. It doesn't rely on central internet servers like Dropbox and can transmit files on the local (W)LAN with insane speed. No registration required-you'll be sharing files in minutes.
Use Trello to manage your tasks. It's super easy to get started and you'll have an easy way to prioritize what should be done next and track what is going on.
Use Slack for team communication. This provides a clear separation of communication for your project, it runs on any device and nobody has share his phone number. Yes, don't even think about using WhatsApp. I mean it!
Bring headphones or earplugs. It will get loud sometimes, and you will need to concentrate. You should bring some music, too. Or just tune in to ETN.
And last but not least: enjoy yourself and take the startup weekend as an exotic escape from your day job. You can be a totally different person here, you know?