Currently you can add and attachment to a client record by "browsing" for it when in the Notes & Attachments tab then uploading it.
I would be EXCELLENT if you could drag and drop documents such as word, excel or PDF to straight int the Notes & Attachments tab from either email or personal drives.
When emailing a client you can "send and upload" the document from your email which will attach the documents to the Notes & Attachments tab but there is no way you can currently drag over files. Often you do not need to attach the whole email and it would be great if you could drag and drop the document from an email or your drives instead of saving them first , browsing then uploading them one at a time.
If you could drag and drop files (and multiple files) directly into the Notes & Attachments tab it would be extremely efficient and a feature I would suggests benefit a number of users.