Recently, I was trying to send a 30 MB PDF file through an email attachment. But Gmail does not allow to upload and send files above 25 MB. One has suggested me to split PDF files into two small files by using a free PDF splitter. I used SystoTech PDF split and merge which really helped me to do the required task.I am amazed with its features like: splitting PDF file into smaller documents, merging multiple PDF files into one or compressing the size of PDF file etc. You can read more details here: http://www.systotech.com/pdf-split-and-merge.aspx