Grafana Cloud, a composable observability platform, offers a free tier that includes up to 10,000 active series and is billed based on usage, prompting questions about costs associated with monitoring different numbers of servers. The platform supports multiple data sources, focusing on Graphite and Prometheus for estimating time series requirements. With Hosted-Graphite, users can monitor approximately 33 servers under the free tier, assuming 300 series per server, whereas Prometheus, which uses more detailed metrics, supports around 13 servers, with node_exporter exporting about 700 active series per server. Users needing more capacity can upgrade to Cloud Pro or Cloud Advanced plans. Grafana Cloud's fully managed LGTM Stack, which includes Grafana Loki, Grafana Tempo, and Grafana Mimir, provides users with comprehensive observability without the hassle of infrastructure management, and allows integration with other tools for metrics, logs, and traces. Additional capabilities include performance testing, incident management, and infrastructure monitoring, with webinars available for further learning about the platform's features.