The Book-at-a-Time Bible Reading plan provides two readings for each day with 25 readings per month. The first reading alternates between an Old and a New Testament book with approximately 3 chapters each day. The second reading comes from the wisdom literature (such as Psalms, Proverbs) and Isaiah. You'll read through the whole Bible in one year.
The Discipleship Journal Bible Reading Plan is one we've used for several years. It provides readings from four separate places in the Scriptures each day including gospel and epistle from the New Testament and wisdom literature and history/prophetic from the Old Testament. This Bible reading plan works a little better for people who are somewhat familiar with the Scriptures. You will read through the whole Bible in one year with 25 readings a month.
A printable pdf of each of these plans is available from the Discipleship Journal website.